Integration by part not working

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Homework Statement


I have three integrals, from 0 to 1
∫ -4x5 ex3-x4dt
∫ 3x4ex3-x4dt
∫ 2tex3-x4dt

Homework Equations


Looks like they are not integrable, as ex3-x4 is not,
I tried by part, let say u =

The Attempt at a Solution


P_20161027_091741.jpg
 
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nysnacc said:

Homework Statement


I have three integrals, from 0 to 1
∫ -4x5 ex3-x4dt
∫ 3x4ex3-x4dt
∫ 2tex3-x4dt

Homework Equations


Looks like they are not integrable, as ex3-x4 is not,
I tried by part, let say u =

The Attempt at a Solution


View attachment 108079
If you have written the integrals exactly as they were given, they should all be very easy. The variable of integration in all three is t (based on the dt part).

As an example, ##\int e^x dt = e^x \int 1 dt = e^x (t + C)##
 
Oh, written wrong, should be dx,sorry
 
Should the last one you listed be ##\int_0^1 2xe^{x^3 - x^4}dx##?

Can you post a photo of the problems? I'm wondering if there's something you left out.
 
Yes, thanks I solved it tho, by recombine the parts in the integral and using by part
 
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