Integration by parts and substitution help

In summary, the conversation is discussing methods for solving the integral ∫0-1 e^√x+1, with suggestions including using substitution or integration by parts. The specific methods depend on the exact form of the integral, which is uncertain in the given context.
  • #1
KAG1188
1
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Integration by parts and substitution help!

Homework Statement




∫0
-1 e ^√x+1




Homework Equations





The Attempt at a Solution

 
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  • #2


I'm sorry, but I simply cannot figure out what that integral is intended to be.

Is that [tex]\int_{-1}^0 e^{\sqrt{x+1}} dx[/tex] or [tex]\int_{-1}^0 e^{\sqrt{x}+ 1} dx[/tex] or [tex]\int_{-1}^0 e^{\sqrt{x}}+ 1 dx[/tex]?

If it is the first, take [itex]u= \sqrt{x+1}= (x+1)^{1/2}[/itex] so that [itex]du= (1/2)(x+1)^{-1/2}dx[/itex] so that [itex](x+1)^{1/2}du= u du= dx[/itex]. When x= -1, u= 0, when x= 0, u= 1 The integral becomes
[tex]\int_0^1 ue^{u}du[/tex]
and can be done by "integration by parts".

If the second, write it as [tex]e\int_{-1}^0 e^{\sqrt{x}}dx[/tex] and let [itex]u= \sqrt{x}[/itex].

If the third, write it as [tex]\int_{-1}^0 e^{\sqrt{x}}dx+ \int_{-1}^0 dx[/tex].
 
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FAQ: Integration by parts and substitution help

What is integration by parts?

Integration by parts is a method used in calculus to find the integral of a product of two functions. It involves breaking down the integral into smaller parts and using a specific formula to solve it.

How does the integration by parts formula work?

The integration by parts formula is ∫udv = uv - ∫vdu. This means that the integral of the product of two functions u and v is equal to the product of u and the antiderivative of v, minus the integral of the antiderivative of v multiplied by the derivative of u.

When should I use integration by parts?

Integration by parts is useful when the integral involves a product of two functions, and one of the functions becomes simpler or easier to integrate after differentiating it. It is also helpful when the integral is in a form that cannot be easily solved using other methods.

What is substitution in calculus?

In calculus, substitution is a method used to simplify integrals by substituting a variable with another expression. This allows for easier integration and can help solve more complex integrals.

How do I know when to use substitution or integration by parts?

The decision to use substitution or integration by parts depends on the specific integral and the functions involved. In some cases, one method may be more straightforward to use, while in others, it may be a matter of personal preference. It is important to practice and gain experience to determine which method is best for a given integral.

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