Math Is Fun Forum

calc2

Guest

integrate

two questions im having trouble with

1)∫(0,1) (4)/((2x-1)^2) dx

and this one

2)∫(ln2,0) 5e^(2x) dx

anyhelp?

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: integrate

Hi calc2:

This integral passes through a discontinuity at x = 1 / 2, it doesn't converge, so it doesn't exist. Check your definite integrals for convergence before you try integrating them.

Say u = 2x

Now for the limits of integration, since u = 2x then when x = 0, u = 0
and when x = log(2) , u = 2 log(2)

So

Last edited by bobbym (2009-09-13 14:51:20)

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

calc2

Guest

Re: integrate

hi bobby thanks for the help. But sorry i didnt word my question right it was to fully evaluate the exact answers that is what im having trouble with.

calc2

Guest

Re: integrate

sorry i also got the points around the wrong way

1) ∫(1,0)
2) ∫(0, ln2)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: integrate

Hi calc2;

1) As far as I understand it does not exist. There is no exact answer. It doesn't converge, its - infinity.

2) Is given above.

Last edited by bobbym (2009-09-13 14:18:02)

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

calc2

Guest

Re: integrate

ok thank you very much bobbym for your help