Need help using substitution before integration

In summary, Substitution is a technique used in calculus to simplify integrals by replacing a variable with another expression. It is important because it allows for the integration of more complex functions and helps to simplify integrals. You can use substitution when you have an integral that contains a function and its derivative or when there is a complicated expression in the integrand that can be simplified by substitution. The steps for using substitution in integration are: identify the variable to be substituted, choose a substitution expression, find the derivative of the substitution expression, substitute the expression and its derivative into the original integral, solve the new integral, and substitute back the original variable into the solution. However, substitution may not always work for all integrals and other techniques may need to be
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abc923
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Hi I just started calc 2 and am stuck on a problem. integral ln(x+x^2)dx. They want to use substitution prior to integrate by parts, but I'm completely stuck. Can anyone help explain how to solve?
 
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abc923 said:
Hi I just started calc 2 and am stuck on a problem. integral ln(x+x^2)dx. They want to use substitution prior to integrate by parts, but I'm completely stuck. Can anyone help explain how to solve?

I'd use the rules of logs first. Factor. x^2+x=(x+1)*x. So? How can you write log(x^2+x) in a simpler way?
 
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Related to Need help using substitution before integration

What is substitution in integration?

Substitution is a technique used in calculus to simplify integrals by replacing a variable with another expression. This allows for easier integration and can help solve more complex integrals.

Why is substitution important in integration?

Substitution is important because it allows for the integration of more complex functions that cannot be solved by traditional methods. It also helps to simplify integrals and make them easier to solve.

How do I know when to use substitution in integration?

You can use substitution when you have an integral that contains a function and its derivative or when there is a complicated expression in the integrand that can be simplified by substitution.

What are the steps for using substitution in integration?

The steps for using substitution in integration are: 1) Identify the variable to be substituted, 2) Choose a substitution expression, 3) Find the derivative of the substitution expression, 4) Substitute the expression and its derivative into the original integral, 5) Solve the new integral, 6) Substitute back the original variable into the solution.

Can substitution be used for all integrals?

No, substitution may not always work for all integrals. It is important to use other integration techniques such as integration by parts or partial fractions if substitution does not yield a simpler integral.

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