How do you find the indefinite integral of ∫sin 4xe^sin2x dx?
2 Answers
I=e^(sin(2x))(sin(2x)-1)+CI=esin(2x)(sin(2x)−1)+C
Explanation:
We want to solve
I=intsin(4x)e^(sin(2x))dxI=∫sin(4x)esin(2x)dx
Using the trig identity
I=2intcos(2x)sin(2x)e^(sin(2x))dxI=2∫cos(2x)sin(2x)esin(2x)dx
Make a substitution
I=intue^(u)duI=∫ueudu
I=ue^u-inte^uduI=ueu−∫eudu
color(white)(I)=ue^u-e^u+CI=ueu−eu+C
color(white)(I)=e^u(u-1)+CI=eu(u−1)+C
Substitute back
I=e^(sin(2x))(sin(2x)-1)+CI=esin(2x)(sin(2x)−1)+C