Great video! But you have made a mistake at 22:40. In equation (2) the LHS should be -2^2/w0^2 A sin(theta) + w/w0Q A cos(theta) + Asin(theta). Also in step (4) once you perform the integration you should get an additional +\int A F_diss sin(theta) dtheta. However, this term is zero if you assume F_diss as an odd function.
Great video! But you have made a mistake at 22:40. In equation (2) the LHS should be -2^2/w0^2 A sin(theta) + w/w0Q A cos(theta) + Asin(theta).
Also in step (4) once you perform the integration you should get an additional +\int A F_diss sin(theta) dtheta. However, this term is zero if you assume F_diss as an odd function.