Calculus Examples

$y = x^{2} + 7 x - 4$ , $y = x + 2$

Step 1

Solve by substitution to find the intersection between the curves.

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Step 1.1

Eliminate the equal sides of each equation and combine.

$x^{2} + 7 x - 4 = x + 2$

Step 1.2

Solve $x^{2} + 7 x - 4 = x + 2$ for $x$ .

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Step 1.2.1

Move all terms containing $x$ to the left side of the equation.

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Step 1.2.1.1

Subtract $x$ from both sides of the equation.

$x^{2} + 7 x - 4 - x = 2$

Step 1.2.1.2

Subtract $x$ from $7 x$ .

$x^{2} + 6 x - 4 = 2$

Step 1.2.2

Move all terms to the left side of the equation and simplify.

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Step 1.2.2.1

Subtract $2$ from both sides of the equation.

$x^{2} + 6 x - 4 - 2 = 0$

Step 1.2.2.2

Subtract $2$ from $- 4$ .

$x^{2} + 6 x - 6 = 0$

Step 1.2.3

Use the quadratic formula to find the solutions.

$\frac{- b \pm \sqrt{b^{2} - 4 (a c)}}{2 a} + y = x + 2$

Step 1.2.4

Substitute the values $a = 1$ , $b = 6$ , and $c = - 6$ into the quadratic formula and solve for $x$ .

$\frac{- 6 \pm \sqrt{6^{2} - 4 \cdot (1 \cdot - 6)}}{2 \cdot 1} + y = x + 2$

Step 1.2.5

Simplify.

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Step 1.2.5.1

Simplify the numerator.

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Step 1.2.5.1.1

Raise $6$ to the power of $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot 1 \cdot - 6}}{2 \cdot 1}$

Step 1.2.5.1.2

Multiply $- 4 \cdot 1 \cdot - 6$ .

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Step 1.2.5.1.2.1

Multiply $- 4$ by $1$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot - 6}}{2 \cdot 1}$

Step 1.2.5.1.2.2

Multiply $- 4$ by $- 6$ .

$x = \frac{- 6 \pm \sqrt{36 + 24}}{2 \cdot 1}$

Step 1.2.5.1.3

Add $36$ and $24$ .

$x = \frac{- 6 \pm \sqrt{60}}{2 \cdot 1}$

Step 1.2.5.1.4

Rewrite $60$ as $2^{2} \cdot 15$ .

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Step 1.2.5.1.4.1

Factor $4$ out of $60$ .

$x = \frac{- 6 \pm \sqrt{4 (15)}}{2 \cdot 1}$

Step 1.2.5.1.4.2

Rewrite $4$ as $2^{2}$ .

$x = \frac{- 6 \pm \sqrt{2^{2} \cdot 15}}{2 \cdot 1}$

Step 1.2.5.1.5

Pull terms out from under the radical.

$x = \frac{- 6 \pm 2 \sqrt{15}}{2 \cdot 1}$

Step 1.2.5.2

Multiply $2$ by $1$ .

$x = \frac{- 6 \pm 2 \sqrt{15}}{2}$

Step 1.2.5.3

Simplify $\frac{- 6 \pm 2 \sqrt{15}}{2}$ .

$x = - 3 \pm \sqrt{15}$

Step 1.2.6

Simplify the expression to solve for the $+$ portion of the $\pm$ .

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Step 1.2.6.1

Simplify the numerator.

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Step 1.2.6.1.1

Raise $6$ to the power of $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot 1 \cdot - 6}}{2 \cdot 1}$

Step 1.2.6.1.2

Multiply $- 4 \cdot 1 \cdot - 6$ .

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Step 1.2.6.1.2.1

Multiply $- 4$ by $1$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot - 6}}{2 \cdot 1}$

Step 1.2.6.1.2.2

Multiply $- 4$ by $- 6$ .

$x = \frac{- 6 \pm \sqrt{36 + 24}}{2 \cdot 1}$

Step 1.2.6.1.3

Add $36$ and $24$ .

$x = \frac{- 6 \pm \sqrt{60}}{2 \cdot 1}$

Step 1.2.6.1.4

Rewrite $60$ as $2^{2} \cdot 15$ .

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Step 1.2.6.1.4.1

Factor $4$ out of $60$ .

$x = \frac{- 6 \pm \sqrt{4 (15)}}{2 \cdot 1}$

Step 1.2.6.1.4.2

Rewrite $4$ as $2^{2}$ .

$x = \frac{- 6 \pm \sqrt{2^{2} \cdot 15}}{2 \cdot 1}$

Step 1.2.6.1.5

Pull terms out from under the radical.

$x = \frac{- 6 \pm 2 \sqrt{15}}{2 \cdot 1}$

Step 1.2.6.2

Multiply $2$ by $1$ .

$x = \frac{- 6 \pm 2 \sqrt{15}}{2}$

Step 1.2.6.3

Simplify $\frac{- 6 \pm 2 \sqrt{15}}{2}$ .

$x = - 3 \pm \sqrt{15}$

Step 1.2.6.4

Change the $\pm$ to $+$ .

$x = - 3 + \sqrt{15}$

Step 1.2.7

Simplify the expression to solve for the $-$ portion of the $\pm$ .

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Step 1.2.7.1

Simplify the numerator.

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Step 1.2.7.1.1

Raise $6$ to the power of $2$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot 1 \cdot - 6}}{2 \cdot 1}$

Step 1.2.7.1.2

Multiply $- 4 \cdot 1 \cdot - 6$ .

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Step 1.2.7.1.2.1

Multiply $- 4$ by $1$ .

$x = \frac{- 6 \pm \sqrt{36 - 4 \cdot - 6}}{2 \cdot 1}$

Step 1.2.7.1.2.2

Multiply $- 4$ by $- 6$ .

$x = \frac{- 6 \pm \sqrt{36 + 24}}{2 \cdot 1}$

Step 1.2.7.1.3

Add $36$ and $24$ .

$x = \frac{- 6 \pm \sqrt{60}}{2 \cdot 1}$

Step 1.2.7.1.4

Rewrite $60$ as $2^{2} \cdot 15$ .

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Step 1.2.7.1.4.1

Factor $4$ out of $60$ .

$x = \frac{- 6 \pm \sqrt{4 (15)}}{2 \cdot 1}$

Step 1.2.7.1.4.2

Rewrite $4$ as $2^{2}$ .

$x = \frac{- 6 \pm \sqrt{2^{2} \cdot 15}}{2 \cdot 1}$

Step 1.2.7.1.5

Pull terms out from under the radical.

$x = \frac{- 6 \pm 2 \sqrt{15}}{2 \cdot 1}$

Step 1.2.7.2

Multiply $2$ by $1$ .

$x = \frac{- 6 \pm 2 \sqrt{15}}{2}$

Step 1.2.7.3

Simplify $\frac{- 6 \pm 2 \sqrt{15}}{2}$ .

$x = - 3 \pm \sqrt{15}$

Step 1.2.7.4

Change the $\pm$ to $-$ .

$x = - 3 - \sqrt{15}$

Step 1.2.8

The final answer is the combination of both solutions.

$x = - 3 + \sqrt{15}, - 3 - \sqrt{15}$

Step 1.3

Evaluate $y$ when $x = - 3 + \sqrt{15}$ .

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Step 1.3.1

Substitute $- 3 + \sqrt{15}$ for $x$ .

$y = (- 3 + \sqrt{15}) + 2$

Step 1.3.2

Substitute $- 3 + \sqrt{15}$ for $x$ in $y = (- 3 + \sqrt{15}) + 2$ and solve for $y$ .

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Step 1.3.2.1

Remove parentheses.

$y = - 3 + \sqrt{15} + 2$

Step 1.3.2.2

Remove parentheses.

$y = (- 3 + \sqrt{15}) + 2$

Step 1.3.2.3

Add $- 3$ and $2$ .

$y = - 1 + \sqrt{15}$

Step 1.4

Evaluate $y$ when $x = - 3 - \sqrt{15}$ .

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Step 1.4.1

Substitute $- 3 - \sqrt{15}$ for $x$ .

$y = (- 3 - \sqrt{15}) + 2$

Step 1.4.2

Substitute $- 3 - \sqrt{15}$ for $x$ in $y = (- 3 - \sqrt{15}) + 2$ and solve for $y$ .

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Step 1.4.2.1

Remove parentheses.

$y = - 3 - \sqrt{15} + 2$

Step 1.4.2.2

Remove parentheses.

$y = (- 3 - \sqrt{15}) + 2$

Step 1.4.2.3

Add $- 3$ and $2$ .

$y = - 1 - \sqrt{15}$

Step 1.5

The solution to the system is the complete set of ordered pairs that are valid solutions.

$(- 3 + \sqrt{15}, - 1 + \sqrt{15})$

$(- 3 - \sqrt{15}, - 1 - \sqrt{15})$

$(- 3 + \sqrt{15}, - 1 + \sqrt{15})$

$(- 3 - \sqrt{15}, - 1 - \sqrt{15})$

Step 2

The area of the region between the curves is defined as the integral of the upper curve minus the integral of the lower curve over each region. The regions are determined by the intersection points of the curves. This can be done algebraically or graphically.

$A r e a = \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} x + 2 d x - \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} x^{2} + 7 x - 4 d x$

Step 3

Integrate to find the area between $- 3 - \sqrt{15}$ and $- 3 + \sqrt{15}$ .

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Step 3.1

Combine the integrals into a single integral.

$\int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} x + 2 - (x^{2} + 7 x - 4) d x$

Step 3.2

Simplify each term.

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Step 3.2.1

Apply the distributive property.

$x + 2 - x^{2} - (7 x) - - 4$

Step 3.2.2

Simplify.

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Step 3.2.2.1

Multiply $7$ by $- 1$ .

$x + 2 - x^{2} - 7 x - - 4$

Step 3.2.2.2

Multiply $- 1$ by $- 4$ .

$x + 2 - x^{2} - 7 x + 4$

$\int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} x + 2 - x^{2} - 7 x + 4 d x$

Step 3.3

Simplify by adding terms.

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Step 3.3.1

Subtract $7 x$ from $x$ .

$- 6 x + 2 - x^{2} + 4$

Step 3.3.2

Add $2$ and $4$ .

$- 6 x - x^{2} + 6$

$\int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} - 6 x - x^{2} + 6 d x$

Step 3.4

Split the single integral into multiple integrals.

$\int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} - 6 x d x + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} - x^{2} d x + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} 6 d x$

Step 3.5

Since $- 6$ is constant with respect to $x$ , move $- 6$ out of the integral.

$- 6 \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} x d x + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} - x^{2} d x + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} 6 d x$

Step 3.6

By the Power Rule, the integral of $x$ with respect to $x$ is $\frac{1}{2} x^{2}$ .

$- 6 (\frac{1}{2} x^{2}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} - x^{2} d x + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} 6 d x$

Step 3.7

Combine $\frac{1}{2}$ and $x^{2}$ .

$- 6 (\frac{x^{2}}{2}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} - x^{2} d x + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} 6 d x$

Step 3.8

Since $- 1$ is constant with respect to $x$ , move $- 1$ out of the integral.

$- 6 (\frac{x^{2}}{2}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) - \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} x^{2} d x + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} 6 d x$

Step 3.9

By the Power Rule, the integral of $x^{2}$ with respect to $x$ is $\frac{1}{3} x^{3}$ .

$- 6 (\frac{x^{2}}{2}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) - (\frac{1}{3} x^{3}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} 6 d x$

Step 3.10

Combine $\frac{1}{3}$ and $x^{3}$ .

$- 6 (\frac{x^{2}}{2}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) - (\frac{x^{3}}{3}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) + \int_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}} 6 d x$

Step 3.11

Apply the constant rule.

$- 6 (\frac{x^{2}}{2}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) - (\frac{x^{3}}{3}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) + 6 x]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}$

Step 3.12

Simplify the answer.

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Step 3.12.1

Substitute and simplify.

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Step 3.12.1.1

Evaluate $\frac{x^{2}}{2}$ at $- 3 + \sqrt{15}$ and at $- 3 - \sqrt{15}$ .

$- 6 ((\frac{{(- 3 + \sqrt{15})}^{2}}{2}) - \frac{{(- 3 - \sqrt{15})}^{2}}{2}) - (\frac{x^{3}}{3}]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}) + 6 x]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}$

Step 3.12.1.2

Evaluate $\frac{x^{3}}{3}$ at $- 3 + \sqrt{15}$ and at $- 3 - \sqrt{15}$ .

$- 6 (\frac{{(- 3 + \sqrt{15})}^{2}}{2} - \frac{{(- 3 - \sqrt{15})}^{2}}{2}) - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + 6 x]_{- 3 - \sqrt{15}}^{- 3 + \sqrt{15}}$

Step 3.12.1.3

Evaluate $6 x$ at $- 3 + \sqrt{15}$ and at $- 3 - \sqrt{15}$ .

$- 6 (\frac{{(- 3 + \sqrt{15})}^{2}}{2} - \frac{{(- 3 - \sqrt{15})}^{2}}{2}) - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4

Simplify.

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Step 3.12.1.4.1

Combine the numerators over the common denominator.

$- 6 \frac{{(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}}{2} - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.2

Combine $- 6$ and $\frac{{(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}}{2}$ .

$\frac{- 6 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})}{2} - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.3

Cancel the common factor of $- 6$ and $2$ .

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Step 3.12.1.4.3.1

Factor $2$ out of $- 6 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})$ .

$\frac{2 (- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}))}{2} - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.3.2

Cancel the common factors.

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Step 3.12.1.4.3.2.1

Factor $2$ out of $2$ .

$\frac{2 (- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}))}{2 (1)} - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.3.2.2

Cancel the common factor.

$\frac{2 (- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}))}{2 \cdot 1} - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.3.2.3

Rewrite the expression.

$\frac{- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})}{1} - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.3.2.4

Divide $- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})$ by $1$ .

$- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - (\frac{{(- 3 + \sqrt{15})}^{3}}{3} - \frac{{(- 3 - \sqrt{15})}^{3}}{3}) + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.4

Combine the numerators over the common denominator.

$- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - \frac{{(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}}{3} + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.5

To write $- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})$ as a fraction with a common denominator, multiply by $\frac{3}{3}$ .

$- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) \cdot \frac{3}{3} - \frac{{(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}}{3} + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.6

Combine $- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})$ and $\frac{3}{3}$ .

$\frac{- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) \cdot 3}{3} - \frac{{(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}}{3} + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.7

Combine the numerators over the common denominator.

$\frac{- 3 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) \cdot 3 - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3})}{3} + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.8

Multiply $3$ by $- 3$ .

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3})}{3} + (6 (- 3 + \sqrt{15})) - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.9

To write $6 (- 3 + \sqrt{15})$ as a fraction with a common denominator, multiply by $\frac{3}{3}$ .

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3})}{3} + 6 (- 3 + \sqrt{15}) \cdot \frac{3}{3} - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.10

Combine $6 (- 3 + \sqrt{15})$ and $\frac{3}{3}$ .

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3})}{3} + \frac{6 (- 3 + \sqrt{15}) \cdot 3}{3} - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.11

Combine the numerators over the common denominator.

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) + 6 (- 3 + \sqrt{15}) \cdot 3}{3} - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.12

Multiply $3$ by $6$ .

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) + 18 (- 3 + \sqrt{15})}{3} - 6 (- 3 - \sqrt{15})$

Step 3.12.1.4.13

To write $- 6 (- 3 - \sqrt{15})$ as a fraction with a common denominator, multiply by $\frac{3}{3}$ .

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) + 18 (- 3 + \sqrt{15})}{3} - 6 (- 3 - \sqrt{15}) \cdot \frac{3}{3}$

Step 3.12.1.4.14

Combine $- 6 (- 3 - \sqrt{15})$ and $\frac{3}{3}$ .

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) + 18 (- 3 + \sqrt{15})}{3} + \frac{- 6 (- 3 - \sqrt{15}) \cdot 3}{3}$

Step 3.12.1.4.15

Combine the numerators over the common denominator.

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) + 18 (- 3 + \sqrt{15}) - 6 (- 3 - \sqrt{15}) \cdot 3}{3}$

Step 3.12.1.4.16

Multiply $3$ by $- 6$ .

$\frac{- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) + 18 (- 3 + \sqrt{15}) - 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.2

Simplify.

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Step 3.12.2.1

Factor $- 1$ out of $- 9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})$ .

$\frac{- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) + 18 (- 3 + \sqrt{15}) - 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.2.2

Factor $- 1$ out of $- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2})) - ({(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3})$ .

$\frac{- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) + 18 (- 3 + \sqrt{15}) - 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.2.3

Factor $- 1$ out of $18 (- 3 + \sqrt{15})$ .

$\frac{- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) - (- 18 (- 3 + \sqrt{15})) - 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.2.4

Factor $- 1$ out of $- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3}) - (- 18 (- 3 + \sqrt{15}))$ .

$\frac{- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15})) - 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.2.5

Factor $- 1$ out of $- 18 (- 3 - \sqrt{15})$ .

$\frac{- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15})) - (18 (- 3 - \sqrt{15}))}{3}$

Step 3.12.2.6

Factor $- 1$ out of $- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15})) - (18 (- 3 - \sqrt{15}))$ .

$\frac{- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15}))}{3}$

Step 3.12.2.7

Rewrite $- (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15}))$ as $- 1 (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15}))$ .

$\frac{- 1 (9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15}))}{3}$

Step 3.12.2.8

Move the negative in front of the fraction.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - {(- 3 - \sqrt{15})}^{2}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3

Simplify.

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Step 3.12.3.1

Rewrite ${(- 3 - \sqrt{15})}^{2}$ as $(- 3 - \sqrt{15}) (- 3 - \sqrt{15})$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - ((- 3 - \sqrt{15}) (- 3 - \sqrt{15}))) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.2

Expand $(- 3 - \sqrt{15}) (- 3 - \sqrt{15})$ using the FOIL Method.

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Step 3.12.3.2.1

Apply the distributive property.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (- 3 (- 3 - \sqrt{15}) - \sqrt{15} (- 3 - \sqrt{15}))) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.2.2

Apply the distributive property.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (- 3 \cdot - 3 - 3 (- \sqrt{15}) - \sqrt{15} (- 3 - \sqrt{15}))) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.2.3

Apply the distributive property.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (- 3 \cdot - 3 - 3 (- \sqrt{15}) - \sqrt{15} \cdot - 3 - \sqrt{15} (- \sqrt{15}))) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3

Simplify and combine like terms.

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Step 3.12.3.3.1

Simplify each term.

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Step 3.12.3.3.1.1

Multiply $- 3$ by $- 3$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 - 3 (- \sqrt{15}) - \sqrt{15} \cdot - 3 - \sqrt{15} (- \sqrt{15}))) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.2

Multiply $- 1$ by $- 3$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} - \sqrt{15} \cdot - 3 - \sqrt{15} (- \sqrt{15}))) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.3

Multiply $- 3$ by $- 1$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} - \sqrt{15} (- \sqrt{15}))) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.4

Multiply $- \sqrt{15} (- \sqrt{15})$ .

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Step 3.12.3.3.1.4.1

Multiply $- 1$ by $- 1$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + 1 \sqrt{15} \sqrt{15})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.4.2

Multiply $\sqrt{15}$ by $1$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + \sqrt{15} \sqrt{15})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.4.3

Raise $\sqrt{15}$ to the power of $1$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + {\sqrt{15}}^{1} \sqrt{15})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.4.4

Raise $\sqrt{15}$ to the power of $1$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + {\sqrt{15}}^{1} {\sqrt{15}}^{1})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.4.5

Use the power rule $a^{m} a^{n} = a^{m + n}$ to combine exponents.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + {\sqrt{15}}^{1 + 1})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.4.6

Add $1$ and $1$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + {\sqrt{15}}^{2})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.5

Rewrite ${\sqrt{15}}^{2}$ as $15$ .

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Step 3.12.3.3.1.5.1

Use $\sqrt[n]{a^{x}} = a^{\frac{x}{n}}$ to rewrite $\sqrt{15}$ as $15^{\frac{1}{2}}$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + {(15^{\frac{1}{2}})}^{2})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.5.2

Apply the power rule and multiply exponents, ${(a^{m})}^{n} = a^{m n}$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + 15^{\frac{1}{2} \cdot 2})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.5.3

Combine $\frac{1}{2}$ and $2$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + 15^{\frac{2}{2}})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.5.4

Cancel the common factor of $2$ .

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Step 3.12.3.3.1.5.4.1

Cancel the common factor.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + 15^{\frac{2}{2}})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.5.4.2

Rewrite the expression.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + 15^{1})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.1.5.5

Evaluate the exponent.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (9 + 3 \sqrt{15} + 3 \sqrt{15} + 15)) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.2

Add $9$ and $15$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (24 + 3 \sqrt{15} + 3 \sqrt{15})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.3.3

Add $3 \sqrt{15}$ and $3 \sqrt{15}$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - (24 + 6 \sqrt{15})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.4

Apply the distributive property.

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - 1 \cdot 24 - (6 \sqrt{15})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.5

Multiply $- 1$ by $24$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - 24 - (6 \sqrt{15})) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.6

Multiply $6$ by $- 1$ .

$- \frac{9 ({(- 3 + \sqrt{15})}^{2} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7

Simplify each term.

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Step 3.12.3.7.1

Rewrite ${(- 3 + \sqrt{15})}^{2}$ as $(- 3 + \sqrt{15}) (- 3 + \sqrt{15})$ .

$- \frac{9 ((- 3 + \sqrt{15}) (- 3 + \sqrt{15}) - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.2

Expand $(- 3 + \sqrt{15}) (- 3 + \sqrt{15})$ using the FOIL Method.

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Step 3.12.3.7.2.1

Apply the distributive property.

$- \frac{9 (- 3 (- 3 + \sqrt{15}) + \sqrt{15} (- 3 + \sqrt{15}) - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.2.2

Apply the distributive property.

$- \frac{9 (- 3 \cdot - 3 - 3 \sqrt{15} + \sqrt{15} (- 3 + \sqrt{15}) - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.2.3

Apply the distributive property.

$- \frac{9 (- 3 \cdot - 3 - 3 \sqrt{15} + \sqrt{15} \cdot - 3 + \sqrt{15} \sqrt{15} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.3

Simplify and combine like terms.

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Step 3.12.3.7.3.1

Simplify each term.

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Step 3.12.3.7.3.1.1

Multiply $- 3$ by $- 3$ .

$- \frac{9 (9 - 3 \sqrt{15} + \sqrt{15} \cdot - 3 + \sqrt{15} \sqrt{15} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.3.1.2

Move $- 3$ to the left of $\sqrt{15}$ .

$- \frac{9 (9 - 3 \sqrt{15} - 3 \cdot \sqrt{15} + \sqrt{15} \sqrt{15} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.3.1.3

Combine using the product rule for radicals.

$- \frac{9 (9 - 3 \sqrt{15} - 3 \sqrt{15} + \sqrt{15 \cdot 15} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.3.1.4

Multiply $15$ by $15$ .

$- \frac{9 (9 - 3 \sqrt{15} - 3 \sqrt{15} + \sqrt{225} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.3.1.5

Rewrite $225$ as $15^{2}$ .

$- \frac{9 (9 - 3 \sqrt{15} - 3 \sqrt{15} + \sqrt{15^{2}} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.3.1.6

Pull terms out from under the radical, assuming positive real numbers.

$- \frac{9 (9 - 3 \sqrt{15} - 3 \sqrt{15} + 15 - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.3.2

Add $9$ and $15$ .

$- \frac{9 (24 - 3 \sqrt{15} - 3 \sqrt{15} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.7.3.3

Subtract $3 \sqrt{15}$ from $- 3 \sqrt{15}$ .

$- \frac{9 (24 - 6 \sqrt{15} - 24 - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.8

Subtract $24$ from $24$ .

$- \frac{9 (0 - 6 \sqrt{15} - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.9

Subtract $6 \sqrt{15}$ from $0$ .

$- \frac{9 (- 6 \sqrt{15} - 6 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.10

Subtract $6 \sqrt{15}$ from $- 6 \sqrt{15}$ .

$- \frac{9 (- 12 \sqrt{15}) + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.11

Multiply $- 12$ by $9$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - {(- 3 - \sqrt{15})}^{3} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.12

Use the Binomial Theorem.

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} + 3 {(- 3)}^{2} (- \sqrt{15}) + 3 \cdot - 3 {(- \sqrt{15})}^{2} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.13

Raise $- 3$ to the power of $2$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} + 3 \cdot 9 (- \sqrt{15}) + 3 \cdot - 3 {(- \sqrt{15})}^{2} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.14

Multiply $3$ by $9$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} + 27 (- \sqrt{15}) + 3 \cdot - 3 {(- \sqrt{15})}^{2} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.15

Multiply $- 1$ by $27$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} + 3 \cdot - 3 {(- \sqrt{15})}^{2} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.16

Multiply $3$ by $- 3$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 {(- \sqrt{15})}^{2} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.17

Apply the product rule to $- \sqrt{15}$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 ({(- 1)}^{2} {\sqrt{15}}^{2}) + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.18

Raise $- 1$ to the power of $2$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 (1 {\sqrt{15}}^{2}) + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.19

Multiply ${\sqrt{15}}^{2}$ by $1$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 {\sqrt{15}}^{2} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.20

Rewrite ${\sqrt{15}}^{2}$ as $15$ .

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Step 3.12.3.20.1

Use $\sqrt[n]{a^{x}} = a^{\frac{x}{n}}$ to rewrite $\sqrt{15}$ as $15^{\frac{1}{2}}$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 {(15^{\frac{1}{2}})}^{2} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.20.2

Apply the power rule and multiply exponents, ${(a^{m})}^{n} = a^{m n}$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 \cdot 15^{\frac{1}{2} \cdot 2} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.20.3

Combine $\frac{1}{2}$ and $2$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 \cdot 15^{\frac{2}{2}} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.20.4

Cancel the common factor of $2$ .

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Step 3.12.3.20.4.1

Cancel the common factor.

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 \cdot 15^{\frac{2}{2}} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.20.4.2

Rewrite the expression.

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 \cdot 15^{1} + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.20.5

Evaluate the exponent.

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 9 \cdot 15 + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.21

Multiply $- 9$ by $15$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - ({(- 3)}^{3} - 27 \sqrt{15} - 135 + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22

Simplify each term.

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Step 3.12.3.22.1

Raise $- 3$ to the power of $3$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 + {(- \sqrt{15})}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22.2

Apply the product rule to $- \sqrt{15}$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 + {(- 1)}^{3} {\sqrt{15}}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22.3

Raise $- 1$ to the power of $3$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 - {\sqrt{15}}^{3}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22.4

Rewrite ${\sqrt{15}}^{3}$ as $\sqrt{15^{3}}$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 - \sqrt{15^{3}}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22.5

Raise $15$ to the power of $3$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 - \sqrt{3375}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22.6

Rewrite $3375$ as $15^{2} \cdot 15$ .

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Step 3.12.3.22.6.1

Factor $225$ out of $3375$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 - \sqrt{225 (15)}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22.6.2

Rewrite $225$ as $15^{2}$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 - \sqrt{15^{2} \cdot 15}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22.7

Pull terms out from under the radical.

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 - (15 \sqrt{15})) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.22.8

Multiply $15$ by $- 1$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 27 - 27 \sqrt{15} - 135 - 15 \sqrt{15}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.23

Subtract $135$ from $- 27$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 162 - 27 \sqrt{15} - 15 \sqrt{15}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.24

Subtract $15 \sqrt{15}$ from $- 27 \sqrt{15}$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - (- 162 - 42 \sqrt{15}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.25

Apply the distributive property.

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} - - 162 - (- 42 \sqrt{15}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.26

Multiply $- 1$ by $- 162$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} + 162 - (- 42 \sqrt{15}) - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.27

Multiply $- 42$ by $- 1$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} + 162 + 42 \sqrt{15} - 18 (- 3 + \sqrt{15}) + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.28

Apply the distributive property.

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} + 162 + 42 \sqrt{15} - 18 \cdot - 3 - 18 \sqrt{15} + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.29

Multiply $- 18$ by $- 3$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} + 18 (- 3 - \sqrt{15})}{3}$

Step 3.12.3.30

Apply the distributive property.

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} + 18 \cdot - 3 + 18 (- \sqrt{15})}{3}$

Step 3.12.3.31

Multiply $18$ by $- 3$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 + 18 (- \sqrt{15})}{3}$

Step 3.12.3.32

Multiply $- 1$ by $18$ .

$- \frac{- 108 \sqrt{15} + {(- 3 + \sqrt{15})}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33

Simplify the numerator.

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Step 3.12.3.33.1

Use the Binomial Theorem.

$- \frac{- 108 \sqrt{15} + {(- 3)}^{3} + 3 {(- 3)}^{2} \sqrt{15} + 3 \cdot - 3 {\sqrt{15}}^{2} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2

Simplify each term.

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Step 3.12.3.33.2.1

Raise $- 3$ to the power of $3$ .

$- \frac{- 108 \sqrt{15} - 27 + 3 {(- 3)}^{2} \sqrt{15} + 3 \cdot - 3 {\sqrt{15}}^{2} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.2

Raise $- 3$ to the power of $2$ .

$- \frac{- 108 \sqrt{15} - 27 + 3 \cdot 9 \sqrt{15} + 3 \cdot - 3 {\sqrt{15}}^{2} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.3

Multiply $3$ by $9$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} + 3 \cdot - 3 {\sqrt{15}}^{2} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.4

Multiply $3$ by $- 3$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 9 {\sqrt{15}}^{2} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.5

Rewrite ${\sqrt{15}}^{2}$ as $15$ .

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Step 3.12.3.33.2.5.1

Use $\sqrt[n]{a^{x}} = a^{\frac{x}{n}}$ to rewrite $\sqrt{15}$ as $15^{\frac{1}{2}}$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 9 {(15^{\frac{1}{2}})}^{2} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.5.2

Apply the power rule and multiply exponents, ${(a^{m})}^{n} = a^{m n}$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 9 \cdot 15^{\frac{1}{2} \cdot 2} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.5.3

Combine $\frac{1}{2}$ and $2$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 9 \cdot 15^{\frac{2}{2}} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.5.4

Cancel the common factor of $2$ .

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Step 3.12.3.33.2.5.4.1

Cancel the common factor.

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 9 \cdot 15^{\frac{2}{2}} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.5.4.2

Rewrite the expression.

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 9 \cdot 15^{1} + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.5.5

Evaluate the exponent.

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 9 \cdot 15 + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.6

Multiply $- 9$ by $15$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 135 + {\sqrt{15}}^{3} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.7

Rewrite ${\sqrt{15}}^{3}$ as $\sqrt{15^{3}}$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 135 + \sqrt{15^{3}} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.8

Raise $15$ to the power of $3$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 135 + \sqrt{3375} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.9

Rewrite $3375$ as $15^{2} \cdot 15$ .

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Step 3.12.3.33.2.9.1

Factor $225$ out of $3375$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 135 + \sqrt{225 (15)} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.9.2

Rewrite $225$ as $15^{2}$ .

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 135 + \sqrt{15^{2} \cdot 15} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.2.10

Pull terms out from under the radical.

$- \frac{- 108 \sqrt{15} - 27 + 27 \sqrt{15} - 135 + 15 \sqrt{15} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.3

Subtract $135$ from $- 27$ .

$- \frac{- 108 \sqrt{15} - 162 + 27 \sqrt{15} + 15 \sqrt{15} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.4

Add $27 \sqrt{15}$ and $15 \sqrt{15}$ .

$- \frac{- 108 \sqrt{15} - 162 + 42 \sqrt{15} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.5

Add $- 108 \sqrt{15}$ and $42 \sqrt{15}$ .

$- \frac{- 162 - 66 \sqrt{15} + 162 + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.6

Add $- 162$ and $162$ .

$- \frac{0 - 66 \sqrt{15} + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.7

Subtract $66 \sqrt{15}$ from $0$ .

$- \frac{- 66 \sqrt{15} + 42 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.8

Add $- 66 \sqrt{15}$ and $42 \sqrt{15}$ .

$- \frac{- 24 \sqrt{15} + 54 - 18 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.9

Subtract $18 \sqrt{15}$ from $- 24 \sqrt{15}$ .

$- \frac{54 - 42 \sqrt{15} - 54 - 18 \sqrt{15}}{3}$

Step 3.12.3.33.10

Subtract $54$ from $54$ .

$- \frac{0 - 42 \sqrt{15} - 18 \sqrt{15}}{3}$

Step 3.12.3.33.11

Subtract $42 \sqrt{15}$ from $0$ .

$- \frac{- 42 \sqrt{15} - 18 \sqrt{15}}{3}$

Step 3.12.3.33.12

Subtract $18 \sqrt{15}$ from $- 42 \sqrt{15}$ .

$- \frac{- 60 \sqrt{15}}{3}$

Step 3.12.3.34

Cancel the common factor of $- 60$ and $3$ .

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Step 3.12.3.34.1

Factor $3$ out of $- 60 \sqrt{15}$ .

$- \frac{3 (- 20 \sqrt{15})}{3}$

Step 3.12.3.34.2

Cancel the common factors.

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Step 3.12.3.34.2.1

Factor $3$ out of $3$ .

$- \frac{3 (- 20 \sqrt{15})}{3 (1)}$

Step 3.12.3.34.2.2

Cancel the common factor.

$- \frac{3 (- 20 \sqrt{15})}{3 \cdot 1}$

Step 3.12.3.34.2.3

Rewrite the expression.

$- \frac{- 20 \sqrt{15}}{1}$

Step 3.12.3.34.2.4

Divide $- 20 \sqrt{15}$ by $1$ .

$- (- 20 \sqrt{15})$

Step 3.12.3.35

Multiply $- 20$ by $- 1$ .

$20 \sqrt{15}$

Step 4

The result can be shown in multiple forms.

Exact Form:

$20 \sqrt{15}$

Decimal Form:

$77.45966692 \dots$

Step 5