# Linear Rationalizing Substitution problem for Integration

• Mar 20th 2013, 05:51 AM
Linear Rationalizing Substitution problem for Integration
So I'm working with the following problem - http://i1057.photobucket.com/albums/...ps245f8e94.png

After setting u = 2x + 1, and (1/2)du = dx, and x = ((u-1)/2) I end up with
(1/2)integral{((u-1)\2)3 (u)(1/3)du}

After doing that I get lost. What would be the next step? Do I need to make another substitution?
(I can't do (1/4)((u-1)/2)4 can I?...)
• Mar 20th 2013, 05:56 AM
princeps
Re: Linear Rationalizing Substitution problem for Integration
Quote:

So I'm working with the following problem - http://i1057.photobucket.com/albums/...ps245f8e94.png

After setting u = 2x + 1, and (1/2)du = dx, and x = ((u-1)/2) I end up with
(1/2)integral{((u-1)\2)3 (u)(1/3)du}

After doing that I get lost. What would be the next step? Do I need to make another substitution?
(I can't do (1/4)((u-1)/2)4 can I?...)

Hint :

\$\displaystyle (A-B)^3=A^3-3A^2B+3AB^2-B^3\$
• Mar 20th 2013, 06:05 AM
Re: Linear Rationalizing Substitution problem for Integration
The thing is, I have ((u-1)/2)3. So I can't re-write is as (u-1)3 x (1/2)3... can I?
• Mar 20th 2013, 08:38 AM
jeanshermanF
Re: Linear Rationalizing Substitution problem for Integration
I just have one question can we solve these kind problems by asking questions like these. Why don't you contact some expert who can work on these kind problems, who have already worked on these kind of problems. I suggest you If you have these many difficulties in solving the mathematics problems you can contact https://artifextutors.com and just send you question to them on questions@artifextutors.com I am sure that they will be able to help you. Artifex Tutors Homework help, Assignment help, Online Tutor, Physics, Chemistry, Math, Statistics, Finance, Economics, Accounting

Regards
Jean
• Mar 20th 2013, 08:59 AM
Re: Linear Rationalizing Substitution problem for Integration
I think that the MHF community is willing to help me, and has helped me in the past. In all honesty, directing me to some other site that in no way relates to my problem is not helping me.
• Mar 20th 2013, 09:07 AM
jeanshermanF
Re: Linear Rationalizing Substitution problem for Integration
Every person does have their own view I am not saying you are wrong. I just gave you an alternate in case you get stuck in the future there are some more people who can help you.

Regards
Jean
• Mar 20th 2013, 09:18 AM
Re: Linear Rationalizing Substitution problem for Integration
Well, thank you, I guess.

Anyway, how do I integrate ((u-1)/2)3?
• Mar 20th 2013, 09:29 AM
MINOANMAN
Re: Linear Rationalizing Substitution problem for Integration