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Re: A92: a92-a lot of questions
Robert Caldwell schrieb:
snip
> here:
>
> integral(x^2*(x+1)^(1/2),x) is suppose to give:
>
> 2x^2*(x+1)^(3/2)/3-8x*(x+1)^(5/2)/15+16*(x+1)^7/2)/105
seems a mistake in the last term : must be 8*(x+1)^(7/2)/105, now check again
(;-) A.K.
Sorry, I made a mistake, too, 16 is correct, but I found the same answer that my
TI gave.
=(x+1)^(3/2)*(2/3*x^2-8/15*x*(x+1)+16/105*(x+1)^2)=
(x+1)^(3/2)*(x^2*(2/3-8/15+16/105)+x*(-8/15+32/105)+16/105)=
(x+1)^(3/2)*(30/105*x^2-24/105*x+16/105) and that is the answer the TI always
gives
>
> you can check that by taking the derivative and getting the above, but
> the calculator gives this answer:
>
> 2x^2*(x+1)^(3/2)/7-8x*(x+1)^(3/2)/35+16*(x+1)^(3/2)/105
>
snip
You should not give unprooved things names, coming to your house may be
impossible, but correctly using the partial integration algorithm may be more
useful, besides: this is quit off topic A.K.
>
> if anyone else has the RCD error post about having it.
>
> -Rob
> president
> RCWare
> Scratch Designs
>
>
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