Mathematics
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OpenStudy (anonymous):
integrate e^(-6x)sin(e^(-3x))dx
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hartnn (hartnn):
did you try substuting
u = e^(-3x) ?
hartnn (hartnn):
*substituting
OpenStudy (anonymous):
yes I tried it by parts and I'm not getting the right answer.....
hartnn (hartnn):
by parts, after that substitution, right ?
OpenStudy (anonymous):
\[\int\limits e ^{-6x}\sin(e ^{-3x})dx\]
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OpenStudy (anonymous):
what do you mean?
hartnn (hartnn):
note
e^(-6x) = e^(-3x) * e^(-3x)
hartnn (hartnn):
i mean , you plug in
u = e^-3x
also find du
hartnn (hartnn):
sin e^-3x becomes sin u
OpenStudy (anonymous):
-1/3du=e^(-3x)dx
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hartnn (hartnn):
yesss
hartnn (hartnn):
-1/3 integral u sin u du
did u get that ?
OpenStudy (anonymous):
yes I did =)
hartnn (hartnn):
can you finish now ?
let me know if you have any other doubts on this :)
OpenStudy (anonymous):
so from here I would use integration by parts?
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hartnn (hartnn):
yes
but if you can, i suggest you use standard result directly
OpenStudy (anonymous):
ok how would I do that ?
hartnn (hartnn):
ok, use integration by parts then
hartnn (hartnn):
or
\(\int x \sin x dx = -x \cos x +\sin x + c\)
OpenStudy (anonymous):
ok thank you so much!!!
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hartnn (hartnn):
welcome ^_^
and
\(\Huge \mathcal{\text{Welcome To OpenStudy}\ddot\smile} \)