please help me with this integral problem:

substitution method

??????

i've no idea what the next step are.....(Headbang)

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- July 22nd 2010, 12:21 AMpencil09integral problem
please help me with this integral problem:

substitution method

??????

i've no idea what the next step are.....(Headbang) - July 22nd 2010, 12:47 AMchisigma
Setting...

(1)

... You derive immediately that is...

(2)

... so that is...

(3)

Kind regards

- July 22nd 2010, 12:59 AMpencil09
- July 22nd 2010, 02:06 AMchisigma
The question has a little minor problem: setting...

(1)

... it seems to be that...

a) is ...

b) is*increasing*with x...

Now is a little difficult to extablish which of the two solutions of the equation...

(2)

... meets both the requirements a) and b), because...

c) vanishes in but is*decreasing*with x...

d) is increasing with x but is ...

Since it is requested fo find a primitive of (1) and all primitives are defined unless a constant, in my opinion the solution is...

(3)

... even if I'm not 'cent per cent' sure (Thinking)...