Integral of (x^2)(sqrt(x^3 + 1))dx. Please check my work? Thank you

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Homework Help Overview

The discussion revolves around the integral of the function \(x^2 \sqrt{x^3 + 1}\) with respect to \(x\). Participants are examining the correctness of an integration attempt using substitution.

Discussion Character

  • Exploratory, Mathematical reasoning

Approaches and Questions Raised

  • One participant presents a substitution method to solve the integral, while others confirm the approach and suggest verifying the result through differentiation. There are also reminders about including the constant of integration.

Discussion Status

The discussion is active, with participants affirming the method used and emphasizing the importance of differentiation as a verification step. There is a focus on ensuring completeness in the solution, particularly regarding the constant of integration.

Contextual Notes

Participants are discussing the integral in the context of homework help, indicating a learning environment where verification and thoroughness are encouraged.

Lo.Lee.Ta.
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∫x^2(√(x^3 + 1))


u = x^3 + 1
du = 3x^2dx
(1/3)du = x^2dx

∫√(u)*(1/3)du

= 2/3(u)^3/2 *(1/3)

= 2/9(x^3 + 1)^3/2

Is this the correct answer? Thank you.
 
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Yep, looks like it. You can always differentiate your answer if you're not sure.
 
Lo.Lee.Ta. said:
∫x^2(√(x^3 + 1))


u = x^3 + 1
du = 3x^2dx
(1/3)du = x^2dx

∫√(u)*(1/3)du

= 2/3(u)^3/2 *(1/3)

= 2/9(x^3 + 1)^3/2

Is this the correct answer? Thank you.

Yes, but don't forget about the constant of integration.
 
Thanks, you guys! :)

That's true. I should differentiate when I'm not sure...
 
Lo.Lee.Ta. said:
Thanks, you guys! :)

That's true. I should differentiate when I'm not sure...

You should differentiate even when you are sure! (Sometimes a person can be sure but still have the wrong answer.)

In other words: always differentiate!
 

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