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#1 2011-02-17 20:32:09

Identity
Member
Registered: 2007-04-18
Posts: 934

An integral

It seems my brain has frozen over

Can anyone help me with this integral?

Thanks

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#2 2011-02-17 21:00:26

Bob
Administrator
Registered: 2010-06-20
Posts: 10,623

Re: An integral

hi Identity,

I like to try to remove the horrible bit by substitution, so


that gives you:

That looks like a second substitution of

and I think that does it.

(I hope)

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#3 2011-02-17 21:07:48

Identity
Member
Registered: 2007-04-18
Posts: 934

Re: An integral

Oh that seems to work, thanks bob :]

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#4 2011-02-17 21:13:44

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: An integral

Hi Identity,

or you may substitute x=sin(t)^2, then it reduces to:


and the final answer:


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#5 2011-02-17 21:18:27

Bob
Administrator
Registered: 2010-06-20
Posts: 10,623

Re: An integral

hi Identity,

You're welcome.  Just checked it by differentiating my answer and, after removing all the algebraic bugs, it came back to the right thing.  Phew!  (took two pages!)

Good morning gAr.  (At least, it's morning here in Essex!)  smile

Bob

Last edited by Bob (2011-02-17 21:20:13)


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#6 2011-02-17 21:29:32

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: An integral

Hi,

Good morning bob.

It's 1459 here (India) smile


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

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