Calculus Examples

Find the Inflection Points (x+1)^2(2x-x^2)
Step 1
Write as a function.
Step 2
Find the second derivative.
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Step 2.1
Find the first derivative.
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Step 2.1.1
Rewrite as .
Step 2.1.2
Expand using the FOIL Method.
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Step 2.1.2.1
Apply the distributive property.
Step 2.1.2.2
Apply the distributive property.
Step 2.1.2.3
Apply the distributive property.
Step 2.1.3
Simplify and combine like terms.
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Step 2.1.3.1
Simplify each term.
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Step 2.1.3.1.1
Multiply by .
Step 2.1.3.1.2
Multiply by .
Step 2.1.3.1.3
Multiply by .
Step 2.1.3.1.4
Multiply by .
Step 2.1.3.2
Add and .
Step 2.1.4
Differentiate using the Product Rule which states that is where and .
Step 2.1.5
Differentiate.
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Step 2.1.5.1
By the Sum Rule, the derivative of with respect to is .
Step 2.1.5.2
Since is constant with respect to , the derivative of with respect to is .
Step 2.1.5.3
Differentiate using the Power Rule which states that is where .
Step 2.1.5.4
Multiply by .
Step 2.1.5.5
Since is constant with respect to , the derivative of with respect to is .
Step 2.1.5.6
Differentiate using the Power Rule which states that is where .
Step 2.1.5.7
Multiply by .
Step 2.1.5.8
By the Sum Rule, the derivative of with respect to is .
Step 2.1.5.9
Differentiate using the Power Rule which states that is where .
Step 2.1.5.10
Since is constant with respect to , the derivative of with respect to is .
Step 2.1.5.11
Differentiate using the Power Rule which states that is where .
Step 2.1.5.12
Multiply by .
Step 2.1.5.13
Since is constant with respect to , the derivative of with respect to is .
Step 2.1.5.14
Add and .
Step 2.1.6
Simplify.
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Step 2.1.6.1
Factor out of .
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Step 2.1.6.1.1
Factor out of .
Step 2.1.6.1.2
Factor out of .
Step 2.1.6.1.3
Factor out of .
Step 2.1.6.2
Multiply by .
Step 2.1.6.3
Reorder terms.
Step 2.1.6.4
Simplify each term.
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Step 2.1.6.4.1
Expand by multiplying each term in the first expression by each term in the second expression.
Step 2.1.6.4.2
Simplify each term.
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Step 2.1.6.4.2.1
Multiply by .
Step 2.1.6.4.2.2
Multiply by .
Step 2.1.6.4.2.3
Multiply by by adding the exponents.
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Step 2.1.6.4.2.3.1
Move .
Step 2.1.6.4.2.3.2
Multiply by .
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Step 2.1.6.4.2.3.2.1
Raise to the power of .
Step 2.1.6.4.2.3.2.2
Use the power rule to combine exponents.
Step 2.1.6.4.2.3.3
Add and .
Step 2.1.6.4.2.4
Rewrite using the commutative property of multiplication.
Step 2.1.6.4.2.5
Multiply by by adding the exponents.
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Step 2.1.6.4.2.5.1
Move .
Step 2.1.6.4.2.5.2
Multiply by .
Step 2.1.6.4.2.6
Multiply by .
Step 2.1.6.4.2.7
Multiply by .
Step 2.1.6.4.3
Subtract from .
Step 2.1.6.4.4
Subtract from .
Step 2.1.6.4.5
Expand using the FOIL Method.
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Step 2.1.6.4.5.1
Apply the distributive property.
Step 2.1.6.4.5.2
Apply the distributive property.
Step 2.1.6.4.5.3
Apply the distributive property.
Step 2.1.6.4.6
Simplify and combine like terms.
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Step 2.1.6.4.6.1
Simplify each term.
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Step 2.1.6.4.6.1.1
Rewrite using the commutative property of multiplication.
Step 2.1.6.4.6.1.2
Multiply by by adding the exponents.
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Step 2.1.6.4.6.1.2.1
Move .
Step 2.1.6.4.6.1.2.2
Multiply by .
Step 2.1.6.4.6.1.3
Multiply by .
Step 2.1.6.4.6.1.4
Rewrite using the commutative property of multiplication.
Step 2.1.6.4.6.1.5
Multiply by by adding the exponents.
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Step 2.1.6.4.6.1.5.1
Move .
Step 2.1.6.4.6.1.5.2
Multiply by .
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Step 2.1.6.4.6.1.5.2.1
Raise to the power of .
Step 2.1.6.4.6.1.5.2.2
Use the power rule to combine exponents.
Step 2.1.6.4.6.1.5.3
Add and .
Step 2.1.6.4.6.1.6
Multiply by .
Step 2.1.6.4.6.1.7
Multiply by .
Step 2.1.6.4.6.1.8
Multiply by .
Step 2.1.6.4.6.2
Subtract from .
Step 2.1.6.5
Combine the opposite terms in .
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Step 2.1.6.5.1
Add and .
Step 2.1.6.5.2
Add and .
Step 2.1.6.6
Add and .
Step 2.1.6.7
Subtract from .
Step 2.2
Find the second derivative.
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Step 2.2.1
Differentiate.
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Step 2.2.1.1
By the Sum Rule, the derivative of with respect to is .
Step 2.2.1.2
Since is constant with respect to , the derivative of with respect to is .
Step 2.2.2
Evaluate .
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Step 2.2.2.1
Since is constant with respect to , the derivative of with respect to is .
Step 2.2.2.2
Differentiate using the Power Rule which states that is where .
Step 2.2.2.3
Multiply by .
Step 2.2.3
Evaluate .
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Step 2.2.3.1
Since is constant with respect to , the derivative of with respect to is .
Step 2.2.3.2
Differentiate using the Power Rule which states that is where .
Step 2.2.3.3
Multiply by .
Step 2.2.4
Subtract from .
Step 2.3
The second derivative of with respect to is .
Step 3
Set the second derivative equal to then solve the equation .
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Step 3.1
Set the second derivative equal to .
Step 3.2
Subtract from both sides of the equation.
Step 3.3
Divide each term in by and simplify.
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Step 3.3.1
Divide each term in by .
Step 3.3.2
Simplify the left side.
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Step 3.3.2.1
Cancel the common factor of .
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Step 3.3.2.1.1
Cancel the common factor.
Step 3.3.2.1.2
Divide by .
Step 3.3.3
Simplify the right side.
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Step 3.3.3.1
Cancel the common factor of and .
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Step 3.3.3.1.1
Factor out of .
Step 3.3.3.1.2
Cancel the common factors.
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Step 3.3.3.1.2.1
Factor out of .
Step 3.3.3.1.2.2
Cancel the common factor.
Step 3.3.3.1.2.3
Rewrite the expression.
Step 3.4
Take the specified root of both sides of the equation to eliminate the exponent on the left side.
Step 3.5
Simplify .
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Step 3.5.1
Rewrite as .
Step 3.5.2
Any root of is .
Step 3.5.3
Multiply by .
Step 3.5.4
Combine and simplify the denominator.
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Step 3.5.4.1
Multiply by .
Step 3.5.4.2
Raise to the power of .
Step 3.5.4.3
Raise to the power of .
Step 3.5.4.4
Use the power rule to combine exponents.
Step 3.5.4.5
Add and .
Step 3.5.4.6
Rewrite as .
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Step 3.5.4.6.1
Use to rewrite as .
Step 3.5.4.6.2
Apply the power rule and multiply exponents, .
Step 3.5.4.6.3
Combine and .
Step 3.5.4.6.4
Cancel the common factor of .
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Step 3.5.4.6.4.1
Cancel the common factor.
Step 3.5.4.6.4.2
Rewrite the expression.
Step 3.5.4.6.5
Evaluate the exponent.
Step 3.6
The complete solution is the result of both the positive and negative portions of the solution.
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Step 3.6.1
First, use the positive value of the to find the first solution.
Step 3.6.2
Next, use the negative value of the to find the second solution.
Step 3.6.3
The complete solution is the result of both the positive and negative portions of the solution.
Step 4
Find the points where the second derivative is .
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Step 4.1
Substitute in to find the value of .
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Step 4.1.1
Replace the variable with in the expression.
Step 4.1.2
Simplify the result.
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Step 4.1.2.1
Rewrite as .
Step 4.1.2.2
Expand using the FOIL Method.
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Step 4.1.2.2.1
Apply the distributive property.
Step 4.1.2.2.2
Apply the distributive property.
Step 4.1.2.2.3
Apply the distributive property.
Step 4.1.2.3
Simplify and combine like terms.
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Step 4.1.2.3.1
Simplify each term.
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Step 4.1.2.3.1.1
Multiply .
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Step 4.1.2.3.1.1.1
Multiply by .
Step 4.1.2.3.1.1.2
Raise to the power of .
Step 4.1.2.3.1.1.3
Raise to the power of .
Step 4.1.2.3.1.1.4
Use the power rule to combine exponents.
Step 4.1.2.3.1.1.5
Add and .
Step 4.1.2.3.1.1.6
Multiply by .
Step 4.1.2.3.1.2
Rewrite as .
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Step 4.1.2.3.1.2.1
Use to rewrite as .
Step 4.1.2.3.1.2.2
Apply the power rule and multiply exponents, .
Step 4.1.2.3.1.2.3
Combine and .
Step 4.1.2.3.1.2.4
Cancel the common factor of .
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Step 4.1.2.3.1.2.4.1
Cancel the common factor.
Step 4.1.2.3.1.2.4.2
Rewrite the expression.
Step 4.1.2.3.1.2.5
Evaluate the exponent.
Step 4.1.2.3.1.3
Cancel the common factor of and .
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Step 4.1.2.3.1.3.1
Factor out of .
Step 4.1.2.3.1.3.2
Cancel the common factors.
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Step 4.1.2.3.1.3.2.1
Factor out of .
Step 4.1.2.3.1.3.2.2
Cancel the common factor.
Step 4.1.2.3.1.3.2.3
Rewrite the expression.
Step 4.1.2.3.1.4
Multiply by .
Step 4.1.2.3.1.5
Multiply by .
Step 4.1.2.3.1.6
Multiply by .
Step 4.1.2.3.2
Write as a fraction with a common denominator.
Step 4.1.2.3.3
Combine the numerators over the common denominator.
Step 4.1.2.3.4
Add and .
Step 4.1.2.3.5
Combine the numerators over the common denominator.
Step 4.1.2.4
Simplify terms.
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Step 4.1.2.4.1
Combine the numerators over the common denominator.
Step 4.1.2.4.2
Add and .
Step 4.1.2.5
Simplify each term.
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Step 4.1.2.5.1
Cancel the common factor of .
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Step 4.1.2.5.1.1
Cancel the common factor.
Step 4.1.2.5.1.2
Rewrite the expression.
Step 4.1.2.5.2
Apply the product rule to .
Step 4.1.2.5.3
Rewrite as .
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Step 4.1.2.5.3.1
Use to rewrite as .
Step 4.1.2.5.3.2
Apply the power rule and multiply exponents, .
Step 4.1.2.5.3.3
Combine and .
Step 4.1.2.5.3.4
Cancel the common factor of .
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Step 4.1.2.5.3.4.1
Cancel the common factor.
Step 4.1.2.5.3.4.2
Rewrite the expression.
Step 4.1.2.5.3.5
Evaluate the exponent.
Step 4.1.2.5.4
Raise to the power of .
Step 4.1.2.5.5
Cancel the common factor of and .
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Step 4.1.2.5.5.1
Factor out of .
Step 4.1.2.5.5.2
Cancel the common factors.
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Step 4.1.2.5.5.2.1
Factor out of .
Step 4.1.2.5.5.2.2
Cancel the common factor.
Step 4.1.2.5.5.2.3
Rewrite the expression.
Step 4.1.2.6
Simplify terms.
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Step 4.1.2.6.1
Apply the distributive property.
Step 4.1.2.6.2
Combine and .
Step 4.1.2.7
Multiply .
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Step 4.1.2.7.1
Multiply by .
Step 4.1.2.7.2
Multiply by .
Step 4.1.2.8
Simplify each term.
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Step 4.1.2.8.1
Apply the distributive property.
Step 4.1.2.8.2
Multiply .
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Step 4.1.2.8.2.1
Raise to the power of .
Step 4.1.2.8.2.2
Raise to the power of .
Step 4.1.2.8.2.3
Use the power rule to combine exponents.
Step 4.1.2.8.2.4
Add and .
Step 4.1.2.8.3
Simplify each term.
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Step 4.1.2.8.3.1
Rewrite as .
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Step 4.1.2.8.3.1.1
Use to rewrite as .
Step 4.1.2.8.3.1.2
Apply the power rule and multiply exponents, .
Step 4.1.2.8.3.1.3
Combine and .
Step 4.1.2.8.3.1.4
Cancel the common factor of .
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Step 4.1.2.8.3.1.4.1
Cancel the common factor.
Step 4.1.2.8.3.1.4.2
Rewrite the expression.
Step 4.1.2.8.3.1.5
Evaluate the exponent.
Step 4.1.2.8.3.2
Multiply by .
Step 4.1.2.9
To write as a fraction with a common denominator, multiply by .
Step 4.1.2.10
Write each expression with a common denominator of , by multiplying each by an appropriate factor of .
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Step 4.1.2.10.1
Multiply by .
Step 4.1.2.10.2
Multiply by .
Step 4.1.2.11
Combine the numerators over the common denominator.
Step 4.1.2.12
Simplify the numerator.
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Step 4.1.2.12.1
Apply the distributive property.
Step 4.1.2.12.2
Multiply by .
Step 4.1.2.12.3
Multiply by .
Step 4.1.2.12.4
Apply the distributive property.
Step 4.1.2.12.5
Multiply by .
Step 4.1.2.12.6
Multiply by .
Step 4.1.2.12.7
Subtract from .
Step 4.1.2.12.8
Subtract from .
Step 4.1.2.13
The final answer is .
Step 4.2
The point found by substituting in is . This point can be an inflection point.
Step 4.3
Substitute in to find the value of .
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Step 4.3.1
Replace the variable with in the expression.
Step 4.3.2
Simplify the result.
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Step 4.3.2.1
Rewrite as .
Step 4.3.2.2
Expand using the FOIL Method.
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Step 4.3.2.2.1
Apply the distributive property.
Step 4.3.2.2.2
Apply the distributive property.
Step 4.3.2.2.3
Apply the distributive property.
Step 4.3.2.3
Simplify and combine like terms.
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Step 4.3.2.3.1
Simplify each term.
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Step 4.3.2.3.1.1
Multiply .
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Step 4.3.2.3.1.1.1
Multiply by .
Step 4.3.2.3.1.1.2
Multiply by .
Step 4.3.2.3.1.1.3
Multiply by .
Step 4.3.2.3.1.1.4
Raise to the power of .
Step 4.3.2.3.1.1.5
Raise to the power of .
Step 4.3.2.3.1.1.6
Use the power rule to combine exponents.
Step 4.3.2.3.1.1.7
Add and .
Step 4.3.2.3.1.1.8
Multiply by .
Step 4.3.2.3.1.2
Rewrite as .
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Step 4.3.2.3.1.2.1
Use to rewrite as .
Step 4.3.2.3.1.2.2
Apply the power rule and multiply exponents, .
Step 4.3.2.3.1.2.3
Combine and .
Step 4.3.2.3.1.2.4
Cancel the common factor of .
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Step 4.3.2.3.1.2.4.1
Cancel the common factor.
Step 4.3.2.3.1.2.4.2
Rewrite the expression.
Step 4.3.2.3.1.2.5
Evaluate the exponent.
Step 4.3.2.3.1.3
Cancel the common factor of and .
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Step 4.3.2.3.1.3.1
Factor out of .
Step 4.3.2.3.1.3.2
Cancel the common factors.
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Step 4.3.2.3.1.3.2.1
Factor out of .
Step 4.3.2.3.1.3.2.2
Cancel the common factor.
Step 4.3.2.3.1.3.2.3
Rewrite the expression.
Step 4.3.2.3.1.4
Multiply by .
Step 4.3.2.3.1.5
Multiply by .
Step 4.3.2.3.1.6
Multiply by .
Step 4.3.2.3.2
Write as a fraction with a common denominator.
Step 4.3.2.3.3
Combine the numerators over the common denominator.
Step 4.3.2.3.4
Add and .
Step 4.3.2.3.5
Subtract from .
Step 4.3.2.4
Simplify terms.
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Step 4.3.2.4.1
Simplify each term.
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Step 4.3.2.4.1.1
Cancel the common factor of .
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Step 4.3.2.4.1.1.1
Factor out of .
Step 4.3.2.4.1.1.2
Cancel the common factor.
Step 4.3.2.4.1.1.3
Rewrite the expression.
Step 4.3.2.4.1.2
Rewrite as .
Step 4.3.2.4.2
Simplify each term.
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Step 4.3.2.4.2.1
Cancel the common factor of .
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Step 4.3.2.4.2.1.1
Move the leading negative in into the numerator.
Step 4.3.2.4.2.1.2
Cancel the common factor.
Step 4.3.2.4.2.1.3
Rewrite the expression.
Step 4.3.2.4.2.2
Use the power rule to distribute the exponent.
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Step 4.3.2.4.2.2.1
Apply the product rule to .
Step 4.3.2.4.2.2.2
Apply the product rule to .
Step 4.3.2.4.2.3
Multiply by by adding the exponents.
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Step 4.3.2.4.2.3.1
Move .
Step 4.3.2.4.2.3.2
Multiply by .
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Step 4.3.2.4.2.3.2.1
Raise to the power of .
Step 4.3.2.4.2.3.2.2
Use the power rule to combine exponents.
Step 4.3.2.4.2.3.3
Add and .
Step 4.3.2.4.2.4
Raise to the power of .
Step 4.3.2.4.2.5
Rewrite as .
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Step 4.3.2.4.2.5.1
Use to rewrite as .
Step 4.3.2.4.2.5.2
Apply the power rule and multiply exponents, .
Step 4.3.2.4.2.5.3
Combine and .
Step 4.3.2.4.2.5.4
Cancel the common factor of .
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Step 4.3.2.4.2.5.4.1
Cancel the common factor.
Step 4.3.2.4.2.5.4.2
Rewrite the expression.
Step 4.3.2.4.2.5.5
Evaluate the exponent.
Step 4.3.2.4.2.6
Raise to the power of .
Step 4.3.2.4.2.7
Cancel the common factor of and .
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Step 4.3.2.4.2.7.1
Factor out of .
Step 4.3.2.4.2.7.2
Cancel the common factors.
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Step 4.3.2.4.2.7.2.1
Factor out of .
Step 4.3.2.4.2.7.2.2
Cancel the common factor.
Step 4.3.2.4.2.7.2.3
Rewrite the expression.
Step 4.3.2.5
Expand using the FOIL Method.
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Step 4.3.2.5.1
Apply the distributive property.
Step 4.3.2.5.2
Apply the distributive property.
Step 4.3.2.5.3
Apply the distributive property.
Step 4.3.2.6
Simplify and combine like terms.
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Step 4.3.2.6.1
Simplify each term.
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Step 4.3.2.6.1.1
Combine and .
Step 4.3.2.6.1.2
Multiply .
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Step 4.3.2.6.1.2.1
Multiply by .
Step 4.3.2.6.1.2.2
Multiply by .
Step 4.3.2.6.1.3
Multiply .
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Step 4.3.2.6.1.3.1
Multiply by .
Step 4.3.2.6.1.3.2
Multiply by .
Step 4.3.2.6.1.3.3
Raise to the power of .
Step 4.3.2.6.1.3.4
Raise to the power of .
Step 4.3.2.6.1.3.5
Use the power rule to combine exponents.
Step 4.3.2.6.1.3.6
Add and .
Step 4.3.2.6.1.4
Rewrite as .
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Step 4.3.2.6.1.4.1
Use to rewrite as .
Step 4.3.2.6.1.4.2
Apply the power rule and multiply exponents, .
Step 4.3.2.6.1.4.3
Combine and .
Step 4.3.2.6.1.4.4
Cancel the common factor of .
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Step 4.3.2.6.1.4.4.1
Cancel the common factor.
Step 4.3.2.6.1.4.4.2
Rewrite the expression.
Step 4.3.2.6.1.4.5
Evaluate the exponent.
Step 4.3.2.6.1.5
Multiply .
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Step 4.3.2.6.1.5.1
Multiply by .
Step 4.3.2.6.1.5.2
Multiply by .
Step 4.3.2.6.1.5.3
Combine and .
Step 4.3.2.6.2
Combine the numerators over the common denominator.
Step 4.3.2.6.3
To write as a fraction with a common denominator, multiply by .
Step 4.3.2.6.4
Combine and .
Step 4.3.2.6.5
Combine the numerators over the common denominator.
Step 4.3.2.6.6
Simplify the numerator.
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Step 4.3.2.6.6.1
Multiply by .
Step 4.3.2.6.6.2
Add and .
Step 4.3.2.7
Add and .
Step 4.3.2.8
Cancel the common factor of and .
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Step 4.3.2.8.1
Factor out of .
Step 4.3.2.8.2
Cancel the common factors.
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Step 4.3.2.8.2.1
Factor out of .
Step 4.3.2.8.2.2
Cancel the common factor.
Step 4.3.2.8.2.3
Rewrite the expression.
Step 4.3.2.8.2.4
Divide by .
Step 4.3.2.9
The final answer is .
Step 4.4
The point found by substituting in is . This point can be an inflection point.
Step 4.5
Determine the points that could be inflection points.
Step 5
Split into intervals around the points that could potentially be inflection points.
Step 6
Substitute a value from the interval into the second derivative to determine if it is increasing or decreasing.
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Step 6.1
Replace the variable with in the expression.
Step 6.2
Simplify the result.
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Step 6.2.1
Simplify each term.
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Step 6.2.1.1
Raise to the power of .
Step 6.2.1.2
Multiply by .
Step 6.2.2
Add and .
Step 6.2.3
The final answer is .
Step 6.3
At , the second derivative is . Since this is negative, the second derivative is decreasing on the interval
Decreasing on since
Decreasing on since
Step 7
Substitute a value from the interval into the second derivative to determine if it is increasing or decreasing.
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Step 7.1
Replace the variable with in the expression.
Step 7.2
Simplify the result.
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Step 7.2.1
Simplify each term.
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Step 7.2.1.1
Raising to any positive power yields .
Step 7.2.1.2
Multiply by .
Step 7.2.2
Add and .
Step 7.2.3
The final answer is .
Step 7.3
At , the second derivative is . Since this is positive, the second derivative is increasing on the interval .
Increasing on since
Increasing on since
Step 8
Substitute a value from the interval into the second derivative to determine if it is increasing or decreasing.
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Step 8.1
Replace the variable with in the expression.
Step 8.2
Simplify the result.
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Step 8.2.1
Simplify each term.
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Step 8.2.1.1
Raise to the power of .
Step 8.2.1.2
Multiply by .
Step 8.2.2
Add and .
Step 8.2.3
The final answer is .
Step 8.3
At , the second derivative is . Since this is negative, the second derivative is decreasing on the interval
Decreasing on since
Decreasing on since
Step 9
An inflection point is a point on a curve at which the concavity changes sign from plus to minus or from minus to plus. The inflection points in this case are .
Step 10