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afcwestwarrior
Aug20-08, 10:22 PM
1. The problem statement, all variables and given/known data
∫e^2θ sin 3θ dθ


2. Relevant equations

∫u dv= uv- ∫v du

3. The attempt at a solution
u= e^2θ dv=sin 3θ dθ
du= 2* e^2θ v=(1/3) * - cos 3 θ

e^2θ 1/3) * - cos 3 θ - ∫1/3) * - cos 3θ 2* e^2θ dθ

what now

nicksauce
Aug20-08, 10:24 PM
Try another IBP (I think that should work)

afcwestwarrior
Aug20-08, 10:32 PM
∫1/3) * - cos 3θ 2* e^2θ dθ
u= cos 3θ dv= e^2θ
du= 3*sin 3θ v= e^2θ
cos 3θ e^2θ - ∫ e^2θ 3*sin 3θ
e^2θ 1/3) *(2/3) - cos 3 θ +cos 3θ e^2θ - ∫ e^2θ 3*sin 3θ

statdad
Aug20-08, 10:32 PM
Integrate by parts once more. You will obtain another integral that is a multiple of the original one. Combine common terms (all the integrals on the left) and solve.

afcwestwarrior
Aug20-08, 10:34 PM
is my v correct for the second igb

afcwestwarrior
Aug20-08, 10:40 PM
ibp i mean

Defennder
Aug21-08, 12:28 AM
I'm having some trouble reading your working. I noticed a single "e^2θ 1/3)" term. You should not have any e^(2θ) without an accompanying cos or sin term. Check your working.