We will use integration by parts. The formula for integration by parts is
∫udv=uv−∫vdu. Let u=sinx and dv=e2xdx. Then du=cosxdx and v=∫e2xdx=21e2x. So, ∫e2xsinxdx=21e2xsinx−∫21e2xcosxdx=21e2xsinx−21∫e2xcosxdx. Now we need to integrate ∫e2xcosxdx. We will use integration by parts again. Let u=cosx and dv=e2xdx. Then du=−sinxdx and v=21e2x. So, ∫e2xcosxdx=21e2xcosx−∫21e2x(−sinx)dx=21e2xcosx+21∫e2xsinxdx. Substituting this back into the first equation, we have:
∫e2xsinxdx=21e2xsinx−21(21e2xcosx+21∫e2xsinxdx) ∫e2xsinxdx=21e2xsinx−41e2xcosx−41∫e2xsinxdx Now, we solve for the integral:
∫e2xsinxdx+41∫e2xsinxdx=21e2xsinx−41e2xcosx 45∫e2xsinxdx=21e2xsinx−41e2xcosx ∫e2xsinxdx=54(21e2xsinx−41e2xcosx) ∫e2xsinxdx=52e2xsinx−51e2xcosx+C ∫e2xsinxdx=51e2x(2sinx−cosx)+C