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help me with this integral pls

help me please
Original post by sakurafall
help me please


Have a think about what (x2+3)a(x^2 + 3)^{-a} differentiates to.
Reply 2
Equivalently, if the above doesn't help then consider the sub u=x2+3u = x^2 + 3
Original post by sakurafall
help me please


Original post by Gregorius
Have a think about what (x2+3)a(x^2 + 3)^{-a} differentiates to.


Original post by Zacken
Equivalently, if the above doesn't help then consider the sub u=x2+3u = x^2 + 3


i am interested in this, i don't know how to do this but i'm very intrigued...
Reply 4
Original post by thefatone
i am interested in this, i don't know how to do this but i'm very intrigued...


It's of the form f(x)f(x)ndx\int f'(x) f(x)^{n} \, \mathrm{d}x
Original post by Zacken
It's of the form f(x)f(x)ndx\int f'(x) f(x)^{n} \, \mathrm{d}x


so i need to differentiate this? what would i do?(if this is C3+ then i haven't done this yet, but it won't hurt to learn it now xD)
Reply 6
Original post by thefatone
so i need to differentiate this? what would i do?(if this is C3+ then i haven't done this yet, but it won't hurt to learn it now xD)


When you differentiate f(x)n+1f(x)^{n+1} you get (n+1)f(x)f(x)n(n+1)f'(x)f(x)^{n} so if you're integrating f(x)f(x)nf'(x)f(x)^n you get f(x)n+1n+1+c\frac{f(x)^{n+1}}{n+1} + c
Original post by Zacken
When you differentiate f(x)n+1f(x)^{n+1} you get (n+1)f(x)f(x)n(n+1)f'(x)f(x)^{n} so if you're integrating f(x)f(x)nf'(x)f(x)^n you get f(x)n+1n+1+c\frac{f(x)^{n+1}}{n+1} + c


oh yea of course :smile: that makes sense
so when we integrate it do we just leave it in that form? in a fraction +C?
Original post by thefatone
oh yea of course :smile: that makes sense
so when we integrate it do we just leave it in that form? in a fraction +C?


Yes.

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