Calculus Examples

$D_{x} (\frac{2 x + 5}{x^{2} - 1})$

Step 1

Differentiate using the Constant Multiple Rule.

Tap for more steps...

Step 1.1

Combine $D_{x}$ and $\frac{2 x + 5}{x^{2} - 1}$ .

$\frac{d}{d x} [\frac{D_{x} (2 x + 5)}{x^{2} - 1}]$

Step 1.2

Since $D_{x}$ is constant with respect to $x$ , the derivative of $\frac{D_{x} (2 x + 5)}{x^{2} - 1}$ with respect to $x$ is $D_{x} \frac{d}{d x} [\frac{2 x + 5}{x^{2} - 1}]$ .

$D_{x} \frac{d}{d x} [\frac{2 x + 5}{x^{2} - 1}]$

Step 2

Differentiate using the Quotient Rule which states that $\frac{d}{d x} [\frac{f (x)}{g (x)}]$ is $\frac{g (x) \frac{d}{d x} [f (x)] - f (x) \frac{d}{d x} [g (x)]}{{g (x)}^{2}}$ where $f (x) = 2 x + 5$ and $g (x) = x^{2} - 1$ .

$D_{x} \frac{(x^{2} - 1) \frac{d}{d x} [2 x + 5] - (2 x + 5) \frac{d}{d x} [x^{2} - 1]}{{(x^{2} - 1)}^{2}}$

Step 3

Differentiate.

Tap for more steps...

Step 3.1

By the Sum Rule, the derivative of $2 x + 5$ with respect to $x$ is $\frac{d}{d x} [2 x] + \frac{d}{d x} [5]$ .

$D_{x} \frac{(x^{2} - 1) (\frac{d}{d x} [2 x] + \frac{d}{d x} [5]) - (2 x + 5) \frac{d}{d x} [x^{2} - 1]}{{(x^{2} - 1)}^{2}}$

Step 3.2

Since $2$ is constant with respect to $x$ , the derivative of $2 x$ with respect to $x$ is $2 \frac{d}{d x} [x]$ .

$D_{x} \frac{(x^{2} - 1) (2 \frac{d}{d x} [x] + \frac{d}{d x} [5]) - (2 x + 5) \frac{d}{d x} [x^{2} - 1]}{{(x^{2} - 1)}^{2}}$

Step 3.3

Differentiate using the Power Rule which states that $\frac{d}{d x} [x^{n}]$ is $n x^{n - 1}$ where $n = 1$ .

$D_{x} \frac{(x^{2} - 1) (2 \cdot 1 + \frac{d}{d x} [5]) - (2 x + 5) \frac{d}{d x} [x^{2} - 1]}{{(x^{2} - 1)}^{2}}$

Step 3.4

Multiply $2$ by $1$ .

$D_{x} \frac{(x^{2} - 1) (2 + \frac{d}{d x} [5]) - (2 x + 5) \frac{d}{d x} [x^{2} - 1]}{{(x^{2} - 1)}^{2}}$

Step 3.5

Since $5$ is constant with respect to $x$ , the derivative of $5$ with respect to $x$ is $0$ .

$D_{x} \frac{(x^{2} - 1) (2 + 0) - (2 x + 5) \frac{d}{d x} [x^{2} - 1]}{{(x^{2} - 1)}^{2}}$

Step 3.6

Simplify the expression.

Tap for more steps...

Step 3.6.1

Add $2$ and $0$ .

$D_{x} \frac{(x^{2} - 1) \cdot 2 - (2 x + 5) \frac{d}{d x} [x^{2} - 1]}{{(x^{2} - 1)}^{2}}$

Step 3.6.2

Move $2$ to the left of $x^{2} - 1$ .

$D_{x} \frac{2 \cdot (x^{2} - 1) - (2 x + 5) \frac{d}{d x} [x^{2} - 1]}{{(x^{2} - 1)}^{2}}$

Step 3.7

By the Sum Rule, the derivative of $x^{2} - 1$ with respect to $x$ is $\frac{d}{d x} [x^{2}] + \frac{d}{d x} [- 1]$ .

$D_{x} \frac{2 (x^{2} - 1) - (2 x + 5) (\frac{d}{d x} [x^{2}] + \frac{d}{d x} [- 1])}{{(x^{2} - 1)}^{2}}$

Step 3.8

Differentiate using the Power Rule which states that $\frac{d}{d x} [x^{n}]$ is $n x^{n - 1}$ where $n = 2$ .

$D_{x} \frac{2 (x^{2} - 1) - (2 x + 5) (2 x + \frac{d}{d x} [- 1])}{{(x^{2} - 1)}^{2}}$

Step 3.9

Since $- 1$ is constant with respect to $x$ , the derivative of $- 1$ with respect to $x$ is $0$ .

$D_{x} \frac{2 (x^{2} - 1) - (2 x + 5) (2 x + 0)}{{(x^{2} - 1)}^{2}}$

Step 3.10

Combine fractions.

Tap for more steps...

Step 3.10.1

Add $2 x$ and $0$ .

$D_{x} \frac{2 (x^{2} - 1) - (2 x + 5) (2 x)}{{(x^{2} - 1)}^{2}}$

Step 3.10.2

Multiply $2$ by $- 1$ .

$D_{x} \frac{2 (x^{2} - 1) - 2 (2 x + 5) x}{{(x^{2} - 1)}^{2}}$

Step 3.10.3

Combine $D_{x}$ and $\frac{2 (x^{2} - 1) - 2 (2 x + 5) x}{{(x^{2} - 1)}^{2}}$ .

$\frac{D_{x} (2 (x^{2} - 1) - 2 (2 x + 5) x)}{{(x^{2} - 1)}^{2}}$

Step 4

Simplify.

Tap for more steps...

Step 4.1

Apply the distributive property.

$\frac{D_{x} (2 x^{2} + 2 \cdot - 1 - 2 (2 x + 5) x)}{{(x^{2} - 1)}^{2}}$

Step 4.2

Apply the distributive property.

$\frac{D_{x} (2 x^{2} + 2 \cdot - 1 + (- 2 (2 x) - 2 \cdot 5) x)}{{(x^{2} - 1)}^{2}}$

Step 4.3

Apply the distributive property.

$\frac{D_{x} (2 x^{2} + 2 \cdot - 1 - 2 (2 x) x - 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.4

Apply the distributive property.

$\frac{D_{x} (2 x^{2}) + D_{x} (2 \cdot - 1) + D_{x} (- 2 (2 x) x) + D_{x} (- 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.5

Simplify the numerator.

Tap for more steps...

Step 4.5.1

Simplify each term.

Tap for more steps...

Step 4.5.1.1

Rewrite using the commutative property of multiplication.

$\frac{2 D_{x} x^{2} + D_{x} (2 \cdot - 1) + D_{x} (- 2 (2 x) x) + D_{x} (- 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.5.1.2

Multiply $2$ by $- 1$ .

$\frac{2 D_{x} x^{2} + D_{x} \cdot - 2 + D_{x} (- 2 (2 x) x) + D_{x} (- 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.5.1.3

Move $- 2$ to the left of $D_{x}$ .

$\frac{2 D_{x} x^{2} - 2 \cdot D_{x} + D_{x} (- 2 (2 x) x) + D_{x} (- 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.5.1.4

Rewrite using the commutative property of multiplication.

$\frac{2 D_{x} x^{2} - 2 D_{x} - 2 \cdot 2 D_{x} x \cdot x + D_{x} (- 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.5.1.5

Multiply $x$ by $x$ by adding the exponents.

Tap for more steps...

Step 4.5.1.5.1

Move $x$ .

$\frac{2 D_{x} x^{2} - 2 D_{x} - 2 \cdot 2 D_{x} (x \cdot x) + D_{x} (- 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.5.1.5.2

Multiply $x$ by $x$ .

$\frac{2 D_{x} x^{2} - 2 D_{x} - 2 \cdot 2 D_{x} x^{2} + D_{x} (- 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.5.1.6

Multiply $- 2$ by $2$ .

$\frac{2 D_{x} x^{2} - 2 D_{x} - 4 D_{x} x^{2} + D_{x} (- 2 \cdot 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.5.1.7

Rewrite using the commutative property of multiplication.

$\frac{2 D_{x} x^{2} - 2 D_{x} - 4 D_{x} x^{2} - 2 \cdot 5 D_{x} x}{{(x^{2} - 1)}^{2}}$

Step 4.5.1.8

Multiply $- 2$ by $5$ .

$\frac{2 D_{x} x^{2} - 2 D_{x} - 4 D_{x} x^{2} - 10 D_{x} x}{{(x^{2} - 1)}^{2}}$

Step 4.5.2

Subtract $4 D_{x} x^{2}$ from $2 D_{x} x^{2}$ .

$\frac{- 2 D_{x} - 2 D_{x} x^{2} - 10 D_{x} x}{{(x^{2} - 1)}^{2}}$

Step 4.6

Reorder terms.

$\frac{- 2 D_{x} - 2 x^{2} D_{x} - 10 D_{x} x}{{(x^{2} - 1)}^{2}}$

Step 4.7

Simplify the numerator.

Tap for more steps...

Step 4.7.1

Factor $2 D_{x}$ out of $- 2 D_{x} - 2 x^{2} D_{x} - 10 D_{x} x$ .

Tap for more steps...

Step 4.7.1.1

Factor $2 D_{x}$ out of $- 2 D_{x}$ .

$\frac{2 D_{x} (- 1) - 2 x^{2} D_{x} - 10 D_{x} x}{{(x^{2} - 1)}^{2}}$

Step 4.7.1.2

Factor $2 D_{x}$ out of $- 2 x^{2} D_{x}$ .

$\frac{2 D_{x} (- 1) + 2 D_{x} (- x^{2}) - 10 D_{x} x}{{(x^{2} - 1)}^{2}}$

Step 4.7.1.3

Factor $2 D_{x}$ out of $- 10 D_{x} x$ .

$\frac{2 D_{x} (- 1) + 2 D_{x} (- x^{2}) + 2 D_{x} (- 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.7.1.4

Factor $2 D_{x}$ out of $2 D_{x} (- 1) + 2 D_{x} (- x^{2})$ .

$\frac{2 D_{x} (- 1 - x^{2}) + 2 D_{x} (- 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.7.1.5

Factor $2 D_{x}$ out of $2 D_{x} (- 1 - x^{2}) + 2 D_{x} (- 5 x)$ .

$\frac{2 D_{x} (- 1 - x^{2} - 5 x)}{{(x^{2} - 1)}^{2}}$

Step 4.7.2

Reorder terms.

$\frac{2 D_{x} (- x^{2} - 5 x - 1)}{{(x^{2} - 1)}^{2}}$

Step 4.8

Simplify the denominator.

Tap for more steps...

Step 4.8.1

Rewrite $1$ as $1^{2}$ .

$\frac{2 D_{x} (- x^{2} - 5 x - 1)}{{(x^{2} - 1^{2})}^{2}}$

Step 4.8.2

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = x$ and $b = 1$ .

$\frac{2 D_{x} (- x^{2} - 5 x - 1)}{{((x + 1) (x - 1))}^{2}}$

Step 4.8.3

Apply the product rule to $(x + 1) (x - 1)$ .

$\frac{2 D_{x} (- x^{2} - 5 x - 1)}{{(x + 1)}^{2} {(x - 1)}^{2}}$

Step 4.9

Factor $- 1$ out of $- x^{2}$ .

$\frac{2 D_{x} (- (x^{2}) - 5 x - 1)}{{(x + 1)}^{2} {(x - 1)}^{2}}$

Step 4.10

Factor $- 1$ out of $- 5 x$ .

$\frac{2 D_{x} (- (x^{2}) - (5 x) - 1)}{{(x + 1)}^{2} {(x - 1)}^{2}}$

Step 4.11

Factor $- 1$ out of $- (x^{2}) - (5 x)$ .

$\frac{2 D_{x} (- (x^{2} + 5 x) - 1)}{{(x + 1)}^{2} {(x - 1)}^{2}}$

Step 4.12

Rewrite $- 1$ as $- 1 (1)$ .

$\frac{2 D_{x} (- (x^{2} + 5 x) - 1 (1))}{{(x + 1)}^{2} {(x - 1)}^{2}}$

Step 4.13

Factor $- 1$ out of $- (x^{2} + 5 x) - 1 (1)$ .

$\frac{2 D_{x} (- (x^{2} + 5 x + 1))}{{(x + 1)}^{2} {(x - 1)}^{2}}$

Step 4.14

Rewrite $- (x^{2} + 5 x + 1)$ as $- 1 (x^{2} + 5 x + 1)$ .

$\frac{2 D_{x} (- 1 (x^{2} + 5 x + 1))}{{(x + 1)}^{2} {(x - 1)}^{2}}$

Step 4.15

Move the negative in front of the fraction.

$- \frac{(2 D_{x}) (x^{2} + 5 x + 1)}{{(x + 1)}^{2} {(x - 1)}^{2}}$

Step 4.16

Reorder factors in $- \frac{(2 D_{x}) (x^{2} + 5 x + 1)}{{(x + 1)}^{2} {(x - 1)}^{2}}$ .

$- \frac{2 D_{x} (x^{2} + 5 x + 1)}{{(x + 1)}^{2} {(x - 1)}^{2}}$