#how do i integrate cos(3x^2)
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atomic sinew
The integral can’t be expressed in terms of elementary functions
crimson plover
is it ok if i dm u ?
tawdry forgeBOT
😑 ɿototoЯ | Rototor 😑
crimson plover
Are you just trying to find $\int cos(3x^2) dx$?
nope the questions bigger
atomic sinew
Well post the question then
crimson plover
is it ok if i dm?
atomic sinew
I’d rather not
tawdry forgeBOT
omar_
crimson plover
thats the question
im guessing you do IBP, with D = the left bracket and I = the cos bit?
atomic sinew
Okay this is a lot better
It’s better to just separate the integral in two $\int x^3cos(3x^2) dx$+$\int 7x cos(3x^2) dx$ for the first one use IBP, for the second one set $3x^2$=u or you can just find the anti derivative directly
tawdry forgeBOT
😑 ɿototoЯ | Rototor 😑
crimson plover
oh wait
that makes sense
how do I use IBP for the first one tho?
i still have to integrate cos(3x^2) in such case right?
atomic sinew
Set u’=xcos(3x^2) and v=x^2
crimson plover
uh
can u put in DI method terms pls xd
oh wait nvm i get wym
i differentiate xcos(3x^2) and integrate x^2?
atomic sinew
i differentiate xcos(3x^2) and integrate x^2?
You integrate xcos(3x^2) and differentiate x^2
crimson plover
o yeh thats what i meant mb
okay tyvm that makes a lot more sense
ill give it a shot now thanks
atomic sinew
Np