Calculus Examples

Find the Local Maxima and Minima f(x)=x-6 natural log of x^2+1
Step 1
Find the first derivative of the function.
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Step 1.1
Differentiate.
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Step 1.1.1
By the Sum Rule, the derivative of with respect to is .
Step 1.1.2
Differentiate using the Power Rule which states that is where .
Step 1.2
Evaluate .
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Step 1.2.1
Since is constant with respect to , the derivative of with respect to is .
Step 1.2.2
Differentiate using the chain rule, which states that is where and .
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Step 1.2.2.1
To apply the Chain Rule, set as .
Step 1.2.2.2
The derivative of with respect to is .
Step 1.2.2.3
Replace all occurrences of with .
Step 1.2.3
By the Sum Rule, the derivative of with respect to is .
Step 1.2.4
Differentiate using the Power Rule which states that is where .
Step 1.2.5
Since is constant with respect to , the derivative of with respect to is .
Step 1.2.6
Add and .
Step 1.2.7
Combine and .
Step 1.2.8
Combine and .
Step 1.2.9
Combine and .
Step 1.2.10
Multiply by .
Step 1.2.11
Move the negative in front of the fraction.
Step 1.3
Simplify.
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Step 1.3.1
Combine terms.
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Step 1.3.1.1
Write as a fraction with a common denominator.
Step 1.3.1.2
Combine the numerators over the common denominator.
Step 1.3.2
Reorder terms.
Step 2
Find the second derivative of the function.
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Step 2.1
Differentiate using the Quotient Rule which states that is where and .
Step 2.2
Differentiate.
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Step 2.2.1
By the Sum Rule, the derivative of with respect to is .
Step 2.2.2
Differentiate using the Power Rule which states that is where .
Step 2.2.3
Since is constant with respect to , the derivative of with respect to is .
Step 2.2.4
Differentiate using the Power Rule which states that is where .
Step 2.2.5
Multiply by .
Step 2.2.6
Since is constant with respect to , the derivative of with respect to is .
Step 2.2.7
Add and .
Step 2.2.8
By the Sum Rule, the derivative of with respect to is .
Step 2.2.9
Differentiate using the Power Rule which states that is where .
Step 2.2.10
Since is constant with respect to , the derivative of with respect to is .
Step 2.2.11
Simplify the expression.
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Step 2.2.11.1
Add and .
Step 2.2.11.2
Multiply by .
Step 2.3
Simplify.
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Step 2.3.1
Apply the distributive property.
Step 2.3.2
Apply the distributive property.
Step 2.3.3
Simplify the numerator.
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Step 2.3.3.1
Simplify each term.
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Step 2.3.3.1.1
Expand using the FOIL Method.
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Step 2.3.3.1.1.1
Apply the distributive property.
Step 2.3.3.1.1.2
Apply the distributive property.
Step 2.3.3.1.1.3
Apply the distributive property.
Step 2.3.3.1.2
Simplify each term.
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Step 2.3.3.1.2.1
Rewrite using the commutative property of multiplication.
Step 2.3.3.1.2.2
Multiply by by adding the exponents.
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Step 2.3.3.1.2.2.1
Move .
Step 2.3.3.1.2.2.2
Multiply by .
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Step 2.3.3.1.2.2.2.1
Raise to the power of .
Step 2.3.3.1.2.2.2.2
Use the power rule to combine exponents.
Step 2.3.3.1.2.2.3
Add and .
Step 2.3.3.1.2.3
Move to the left of .
Step 2.3.3.1.2.4
Multiply by .
Step 2.3.3.1.2.5
Multiply by .
Step 2.3.3.1.3
Multiply by by adding the exponents.
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Step 2.3.3.1.3.1
Move .
Step 2.3.3.1.3.2
Multiply by .
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Step 2.3.3.1.3.2.1
Raise to the power of .
Step 2.3.3.1.3.2.2
Use the power rule to combine exponents.
Step 2.3.3.1.3.3
Add and .
Step 2.3.3.1.4
Multiply by by adding the exponents.
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Step 2.3.3.1.4.1
Move .
Step 2.3.3.1.4.2
Multiply by .
Step 2.3.3.1.5
Multiply by .
Step 2.3.3.1.6
Multiply by .
Step 2.3.3.2
Combine the opposite terms in .
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Step 2.3.3.2.1
Subtract from .
Step 2.3.3.2.2
Add and .
Step 2.3.3.2.3
Subtract from .
Step 2.3.3.2.4
Add and .
Step 2.3.3.3
Add and .
Step 2.3.4
Simplify the numerator.
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Step 2.3.4.1
Factor out of .
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Step 2.3.4.1.1
Factor out of .
Step 2.3.4.1.2
Factor out of .
Step 2.3.4.1.3
Factor out of .
Step 2.3.4.2
Rewrite as .
Step 2.3.4.3
Since both terms are perfect squares, factor using the difference of squares formula, where and .
Step 3
To find the local maximum and minimum values of the function, set the derivative equal to and solve.
Step 4
Find the first derivative.
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Step 4.1
Find the first derivative.
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Step 4.1.1
Differentiate.
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Step 4.1.1.1
By the Sum Rule, the derivative of with respect to is .
Step 4.1.1.2
Differentiate using the Power Rule which states that is where .
Step 4.1.2
Evaluate .
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Step 4.1.2.1
Since is constant with respect to , the derivative of with respect to is .
Step 4.1.2.2
Differentiate using the chain rule, which states that is where and .
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Step 4.1.2.2.1
To apply the Chain Rule, set as .
Step 4.1.2.2.2
The derivative of with respect to is .
Step 4.1.2.2.3
Replace all occurrences of with .
Step 4.1.2.3
By the Sum Rule, the derivative of with respect to is .
Step 4.1.2.4
Differentiate using the Power Rule which states that is where .
Step 4.1.2.5
Since is constant with respect to , the derivative of with respect to is .
Step 4.1.2.6
Add and .
Step 4.1.2.7
Combine and .
Step 4.1.2.8
Combine and .
Step 4.1.2.9
Combine and .
Step 4.1.2.10
Multiply by .
Step 4.1.2.11
Move the negative in front of the fraction.
Step 4.1.3
Simplify.
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Step 4.1.3.1
Combine terms.
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Step 4.1.3.1.1
Write as a fraction with a common denominator.
Step 4.1.3.1.2
Combine the numerators over the common denominator.
Step 4.1.3.2
Reorder terms.
Step 4.2
The first derivative of with respect to is .
Step 5
Set the first derivative equal to then solve the equation .
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Step 5.1
Set the first derivative equal to .
Step 5.2
Set the numerator equal to zero.
Step 5.3
Solve the equation for .
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Step 5.3.1
Use the quadratic formula to find the solutions.
Step 5.3.2
Substitute the values , , and into the quadratic formula and solve for .
Step 5.3.3
Simplify.
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Step 5.3.3.1
Simplify the numerator.
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Step 5.3.3.1.1
Raise to the power of .
Step 5.3.3.1.2
Multiply .
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Step 5.3.3.1.2.1
Multiply by .
Step 5.3.3.1.2.2
Multiply by .
Step 5.3.3.1.3
Subtract from .
Step 5.3.3.1.4
Rewrite as .
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Step 5.3.3.1.4.1
Factor out of .
Step 5.3.3.1.4.2
Rewrite as .
Step 5.3.3.1.5
Pull terms out from under the radical.
Step 5.3.3.2
Multiply by .
Step 5.3.3.3
Simplify .
Step 5.3.4
Simplify the expression to solve for the portion of the .
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Step 5.3.4.1
Simplify the numerator.
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Step 5.3.4.1.1
Raise to the power of .
Step 5.3.4.1.2
Multiply .
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Step 5.3.4.1.2.1
Multiply by .
Step 5.3.4.1.2.2
Multiply by .
Step 5.3.4.1.3
Subtract from .
Step 5.3.4.1.4
Rewrite as .
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Step 5.3.4.1.4.1
Factor out of .
Step 5.3.4.1.4.2
Rewrite as .
Step 5.3.4.1.5
Pull terms out from under the radical.
Step 5.3.4.2
Multiply by .
Step 5.3.4.3
Simplify .
Step 5.3.4.4
Change the to .
Step 5.3.5
Simplify the expression to solve for the portion of the .
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Step 5.3.5.1
Simplify the numerator.
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Step 5.3.5.1.1
Raise to the power of .
Step 5.3.5.1.2
Multiply .
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Step 5.3.5.1.2.1
Multiply by .
Step 5.3.5.1.2.2
Multiply by .
Step 5.3.5.1.3
Subtract from .
Step 5.3.5.1.4
Rewrite as .
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Step 5.3.5.1.4.1
Factor out of .
Step 5.3.5.1.4.2
Rewrite as .
Step 5.3.5.1.5
Pull terms out from under the radical.
Step 5.3.5.2
Multiply by .
Step 5.3.5.3
Simplify .
Step 5.3.5.4
Change the to .
Step 5.3.6
The final answer is the combination of both solutions.
Step 6
Find the values where the derivative is undefined.
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Step 6.1
The domain of the expression is all real numbers except where the expression is undefined. In this case, there is no real number that makes the expression undefined.
Step 7
Critical points to evaluate.
Step 8
Evaluate the second derivative at . If the second derivative is positive, then this is a local minimum. If it is negative, then this is a local maximum.
Step 9
Evaluate the second derivative.
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Step 9.1
Simplify the numerator.
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Step 9.1.1
Add and .
Step 9.1.2
Subtract from .
Step 9.2
Simplify the denominator.
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Step 9.2.1
Rewrite as .
Step 9.2.2
Expand using the FOIL Method.
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Step 9.2.2.1
Apply the distributive property.
Step 9.2.2.2
Apply the distributive property.
Step 9.2.2.3
Apply the distributive property.
Step 9.2.3
Simplify and combine like terms.
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Step 9.2.3.1
Simplify each term.
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Step 9.2.3.1.1
Multiply by .
Step 9.2.3.1.2
Move to the left of .
Step 9.2.3.1.3
Combine using the product rule for radicals.
Step 9.2.3.1.4
Multiply by .
Step 9.2.3.1.5
Rewrite as .
Step 9.2.3.1.6
Pull terms out from under the radical, assuming positive real numbers.
Step 9.2.3.2
Add and .
Step 9.2.3.3
Add and .
Step 9.2.4
Add and .
Step 9.3
Group and together.
Step 9.4
Expand using the FOIL Method.
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Step 9.4.1
Apply the distributive property.
Step 9.4.2
Apply the distributive property.
Step 9.4.3
Apply the distributive property.
Step 9.5
Simplify and combine like terms.
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Step 9.5.1
Simplify each term.
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Step 9.5.1.1
Multiply by .
Step 9.5.1.2
Move to the left of .
Step 9.5.1.3
Combine using the product rule for radicals.
Step 9.5.1.4
Multiply by .
Step 9.5.1.5
Rewrite as .
Step 9.5.1.6
Pull terms out from under the radical, assuming positive real numbers.
Step 9.5.2
Add and .
Step 9.5.3
Add and .
Step 9.6
Rewrite as .
Step 9.7
Expand using the FOIL Method.
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Step 9.7.1
Apply the distributive property.
Step 9.7.2
Apply the distributive property.
Step 9.7.3
Apply the distributive property.
Step 9.8
Simplify and combine like terms.
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Step 9.8.1
Simplify each term.
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Step 9.8.1.1
Multiply by .
Step 9.8.1.2
Multiply by .
Step 9.8.1.3
Multiply by .
Step 9.8.1.4
Multiply .
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Step 9.8.1.4.1
Multiply by .
Step 9.8.1.4.2
Raise to the power of .
Step 9.8.1.4.3
Raise to the power of .
Step 9.8.1.4.4
Use the power rule to combine exponents.
Step 9.8.1.4.5
Add and .
Step 9.8.1.5
Rewrite as .
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Step 9.8.1.5.1
Use to rewrite as .
Step 9.8.1.5.2
Apply the power rule and multiply exponents, .
Step 9.8.1.5.3
Combine and .
Step 9.8.1.5.4
Cancel the common factor of .
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Step 9.8.1.5.4.1
Cancel the common factor.
Step 9.8.1.5.4.2
Rewrite the expression.
Step 9.8.1.5.5
Evaluate the exponent.
Step 9.8.1.6
Multiply by .
Step 9.8.2
Add and .
Step 9.8.3
Add and .
Step 9.9
Cancel the common factors.
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Step 9.9.1
Factor out of .
Step 9.9.2
Factor out of .
Step 9.9.3
Factor out of .
Step 9.9.4
Cancel the common factor.
Step 9.9.5
Rewrite the expression.
Step 9.10
Cancel the common factor of and .
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Step 9.10.1
Factor out of .
Step 9.10.2
Factor out of .
Step 9.10.3
Factor out of .
Step 9.10.4
Cancel the common factors.
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Step 9.10.4.1
Factor out of .
Step 9.10.4.2
Factor out of .
Step 9.10.4.3
Factor out of .
Step 9.10.4.4
Cancel the common factor.
Step 9.10.4.5
Rewrite the expression.
Step 9.11
Multiply by .
Step 9.12
Simplify terms.
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Step 9.12.1
Multiply by .
Step 9.12.2
Expand the denominator using the FOIL method.
Step 9.12.3
Simplify.
Step 9.12.4
Cancel the common factor of and .
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Step 9.12.4.1
Factor out of .
Step 9.12.4.2
Cancel the common factors.
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Step 9.12.4.2.1
Factor out of .
Step 9.12.4.2.2
Cancel the common factor.
Step 9.12.4.2.3
Rewrite the expression.
Step 9.13
Expand using the FOIL Method.
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Step 9.13.1
Apply the distributive property.
Step 9.13.2
Apply the distributive property.
Step 9.13.3
Apply the distributive property.
Step 9.14
Simplify and combine like terms.
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Step 9.14.1
Simplify each term.
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Step 9.14.1.1
Multiply by .
Step 9.14.1.2
Multiply by .
Step 9.14.1.3
Multiply by .
Step 9.14.1.4
Multiply .
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Step 9.14.1.4.1
Multiply by .
Step 9.14.1.4.2
Raise to the power of .
Step 9.14.1.4.3
Raise to the power of .
Step 9.14.1.4.4
Use the power rule to combine exponents.
Step 9.14.1.4.5
Add and .
Step 9.14.1.5
Rewrite as .
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Step 9.14.1.5.1
Use to rewrite as .
Step 9.14.1.5.2
Apply the power rule and multiply exponents, .
Step 9.14.1.5.3
Combine and .
Step 9.14.1.5.4
Cancel the common factor of .
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Step 9.14.1.5.4.1
Cancel the common factor.
Step 9.14.1.5.4.2
Rewrite the expression.
Step 9.14.1.5.5
Evaluate the exponent.
Step 9.14.1.6
Multiply by .
Step 9.14.2
Subtract from .
Step 9.14.3
Add and .
Step 9.15
Rewrite as .
Step 9.16
Factor out of .
Step 9.17
Factor out of .
Step 9.18
Move the negative in front of the fraction.
Step 10
is a local minimum because the value of the second derivative is positive. This is referred to as the second derivative test.
is a local minimum
Step 11
Find the y-value when .
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Step 11.1
Replace the variable with in the expression.
Step 11.2
Simplify the result.
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Step 11.2.1
Remove parentheses.
Step 11.2.2
The final answer is .
Step 12
Evaluate the second derivative at . If the second derivative is positive, then this is a local minimum. If it is negative, then this is a local maximum.
Step 13
Evaluate the second derivative.
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Step 13.1
Simplify the numerator.
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Step 13.1.1
Add and .
Step 13.1.2
Subtract from .
Step 13.2
Simplify the denominator.
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Step 13.2.1
Rewrite as .
Step 13.2.2
Expand using the FOIL Method.
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Step 13.2.2.1
Apply the distributive property.
Step 13.2.2.2
Apply the distributive property.
Step 13.2.2.3
Apply the distributive property.
Step 13.2.3
Simplify and combine like terms.
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Step 13.2.3.1
Simplify each term.
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Step 13.2.3.1.1
Multiply by .
Step 13.2.3.1.2
Multiply by .
Step 13.2.3.1.3
Multiply by .
Step 13.2.3.1.4
Multiply .
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Step 13.2.3.1.4.1
Multiply by .
Step 13.2.3.1.4.2
Multiply by .
Step 13.2.3.1.4.3
Raise to the power of .
Step 13.2.3.1.4.4
Raise to the power of .
Step 13.2.3.1.4.5
Use the power rule to combine exponents.
Step 13.2.3.1.4.6
Add and .
Step 13.2.3.1.5
Rewrite as .
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Step 13.2.3.1.5.1
Use to rewrite as .
Step 13.2.3.1.5.2
Apply the power rule and multiply exponents, .
Step 13.2.3.1.5.3
Combine and .
Step 13.2.3.1.5.4
Cancel the common factor of .
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Step 13.2.3.1.5.4.1
Cancel the common factor.
Step 13.2.3.1.5.4.2
Rewrite the expression.
Step 13.2.3.1.5.5
Evaluate the exponent.
Step 13.2.3.2
Add and .
Step 13.2.3.3
Subtract from .
Step 13.2.4
Add and .
Step 13.3
Group and together.
Step 13.4
Expand using the FOIL Method.
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Step 13.4.1
Apply the distributive property.
Step 13.4.2
Apply the distributive property.
Step 13.4.3
Apply the distributive property.
Step 13.5
Simplify and combine like terms.
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Step 13.5.1
Simplify each term.
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Step 13.5.1.1
Multiply by .
Step 13.5.1.2
Multiply by .
Step 13.5.1.3
Multiply by .
Step 13.5.1.4
Multiply .
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Step 13.5.1.4.1
Multiply by .
Step 13.5.1.4.2
Multiply by .
Step 13.5.1.4.3
Raise to the power of .
Step 13.5.1.4.4
Raise to the power of .
Step 13.5.1.4.5
Use the power rule to combine exponents.
Step 13.5.1.4.6
Add and .
Step 13.5.1.5
Rewrite as .
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Step 13.5.1.5.1
Use to rewrite as .
Step 13.5.1.5.2
Apply the power rule and multiply exponents, .
Step 13.5.1.5.3
Combine and .
Step 13.5.1.5.4
Cancel the common factor of .
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Step 13.5.1.5.4.1
Cancel the common factor.
Step 13.5.1.5.4.2
Rewrite the expression.
Step 13.5.1.5.5
Evaluate the exponent.
Step 13.5.2
Add and .
Step 13.5.3
Subtract from .
Step 13.6
Rewrite as .
Step 13.7
Expand using the FOIL Method.
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Step 13.7.1
Apply the distributive property.
Step 13.7.2
Apply the distributive property.
Step 13.7.3
Apply the distributive property.
Step 13.8
Simplify and combine like terms.
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Step 13.8.1
Simplify each term.
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Step 13.8.1.1
Multiply by .
Step 13.8.1.2
Multiply by .
Step 13.8.1.3
Multiply by .
Step 13.8.1.4
Multiply .
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Step 13.8.1.4.1
Multiply by .
Step 13.8.1.4.2
Raise to the power of .
Step 13.8.1.4.3
Raise to the power of .
Step 13.8.1.4.4
Use the power rule to combine exponents.
Step 13.8.1.4.5
Add and .
Step 13.8.1.5
Rewrite as .
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Step 13.8.1.5.1
Use to rewrite as .
Step 13.8.1.5.2
Apply the power rule and multiply exponents, .
Step 13.8.1.5.3
Combine and .
Step 13.8.1.5.4
Cancel the common factor of .
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Step 13.8.1.5.4.1
Cancel the common factor.
Step 13.8.1.5.4.2
Rewrite the expression.
Step 13.8.1.5.5
Evaluate the exponent.
Step 13.8.1.6
Multiply by .
Step 13.8.2
Add and .
Step 13.8.3
Subtract from .
Step 13.9
Cancel the common factors.
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Step 13.9.1
Factor out of .
Step 13.9.2
Factor out of .
Step 13.9.3
Factor out of .
Step 13.9.4
Cancel the common factor.
Step 13.9.5
Rewrite the expression.
Step 13.10
Cancel the common factor of and .
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Step 13.10.1
Factor out of .
Step 13.10.2
Factor out of .
Step 13.10.3
Factor out of .
Step 13.10.4
Cancel the common factors.
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Step 13.10.4.1
Factor out of .
Step 13.10.4.2
Factor out of .
Step 13.10.4.3
Factor out of .
Step 13.10.4.4
Cancel the common factor.
Step 13.10.4.5
Rewrite the expression.
Step 13.11
Multiply by .
Step 13.12
Simplify terms.
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Step 13.12.1
Multiply by .
Step 13.12.2
Expand the denominator using the FOIL method.
Step 13.12.3
Simplify.
Step 13.12.4
Cancel the common factor of and .
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Step 13.12.4.1
Factor out of .
Step 13.12.4.2
Cancel the common factors.
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Step 13.12.4.2.1
Factor out of .
Step 13.12.4.2.2
Cancel the common factor.
Step 13.12.4.2.3
Rewrite the expression.
Step 13.13
Expand using the FOIL Method.
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Step 13.13.1
Apply the distributive property.
Step 13.13.2
Apply the distributive property.
Step 13.13.3
Apply the distributive property.
Step 13.14
Simplify and combine like terms.
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Step 13.14.1
Simplify each term.
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Step 13.14.1.1
Multiply by .
Step 13.14.1.2
Multiply by .
Step 13.14.1.3
Multiply by .
Step 13.14.1.4
Multiply .
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Step 13.14.1.4.1
Multiply by .
Step 13.14.1.4.2
Raise to the power of .
Step 13.14.1.4.3
Raise to the power of .
Step 13.14.1.4.4
Use the power rule to combine exponents.
Step 13.14.1.4.5
Add and .
Step 13.14.1.5
Rewrite as .
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Step 13.14.1.5.1
Use to rewrite as .
Step 13.14.1.5.2
Apply the power rule and multiply exponents, .
Step 13.14.1.5.3
Combine and .
Step 13.14.1.5.4
Cancel the common factor of .
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Step 13.14.1.5.4.1
Cancel the common factor.
Step 13.14.1.5.4.2
Rewrite the expression.
Step 13.14.1.5.5
Evaluate the exponent.
Step 13.14.1.6
Multiply by .
Step 13.14.2
Subtract from .
Step 13.14.3
Subtract from .
Step 13.15
Rewrite as .
Step 13.16
Factor out of .
Step 13.17
Factor out of .
Step 13.18
Move the negative in front of the fraction.
Step 14
is a local maximum because the value of the second derivative is negative. This is referred to as the second derivative test.
is a local maximum
Step 15
Find the y-value when .
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Step 15.1
Replace the variable with in the expression.
Step 15.2
Simplify the result.
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Step 15.2.1
Simplify by moving inside the logarithm.
Step 15.2.2
The final answer is .
Step 16
These are the local extrema for .
is a local minima
is a local maxima
Step 17