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 P: 2,453 If I have $\int e^{2x}sin(x)sin(2x)$ And then I use Eulers formula to substitute in for the sine terms. So I have $\int e^{2x}e^{ix}e^{2ix}$ then I combine everything so i get $e^{(2+3i)x}$ so then we integrate the exponential, so we divide by 2+3i and then i multiply by the complex conjugate. now since sine is the imaginary part of his formula I took the imaginary part when I back substituted for e^(3i) but I didn't get the correct answer doing this, so am i not using Eulers formula correctly?