i got read of one root but instead i got another one

??

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- Feb 18th 2009, 06:37 AMtransgalacticroot integral question..

i got read of one root but instead i got another one

?? - Feb 18th 2009, 06:43 AMJester
- Feb 18th 2009, 09:47 AMtransgalactic
when i substituted i didnt get your expression

i got

- Feb 18th 2009, 10:02 AMJester
- Feb 19th 2009, 11:58 AMtransgalactic
i cant solve this last part:

even when i split it:

and take t=2u^2 -u +1

?? - Feb 19th 2009, 12:31 PMrunning-gag
- Feb 19th 2009, 11:06 PMtransgalactic
i cant get your last part

how you got this coefficients??

2A+2B+c=0

A-B+c+d=0

B=-D

A=6

i got these equation

and i cant get your coefficients

?? - Feb 20th 2009, 07:33 AMrunning-gag

I forgot the "6" as numerator ... sorry

Multiply everything above by 6 - Feb 20th 2009, 12:09 PMtransgalactic
its still does give the last part as i got it

where did my coefficientcient equations differ yours?? - Feb 21st 2009, 01:09 AMtransgalacticdid i get the coefficient equations ..

1:

- Feb 21st 2009, 01:25 AMAir
The denominator factorises to .

Thus, The fraction becomes .

You have a sign error. is ve, and not ve. Your formula produced are correct, just a sign error has made them slightly differ.

You can continue to use gaussian elimination after you've made the correction. :) - Feb 21st 2009, 01:35 AMrunning-gag
Your equations are correct.

There is a much easier way :

Multiply both sides by u

And set u to 0

Multiply both sides by u+1

And set u to -1

- Feb 21st 2009, 04:03 AMtransgalactic
i tried again

http://img13.imageshack.us/img13/2839/29878774.th.gif

here is my full way till i got the coefficients

where did i go wrong

?? - Feb 21st 2009, 04:18 AMrunning-gag
C=-9 is OK

then -3+2D=0 gives D=3/2 and not 2/3 - Feb 21st 2009, 04:45 AMtransgalactic

but then the derivative of the denominator doesnt give us the numenator

??