Integral of (sin8xcos2x)/4 dx
The solution
The graph
/2*pi\ /8*pi\ /2*pi\ /8*pi\
cos|----|*cos|----| sin|----|*sin|----|
1 \ 61 / \ 61 / \ 61 / \ 61 /
-- - ------------------- - -------------------
30 30 120
−30cos(612π)cos(618π)−120sin(612π)sin(618π)+301
=
/2*pi\ /8*pi\ /2*pi\ /8*pi\
cos|----|*cos|----| sin|----|*sin|----|
1 \ 61 / \ 61 / \ 61 / \ 61 /
-- - ------------------- - -------------------
30 30 120
−30cos(612π)cos(618π)−120sin(612π)sin(618π)+301
1/30 - cos(2*pi/61)*cos(8*pi/61)/30 - sin(2*pi/61)*sin(8*pi/61)/120
Use the examples entering the upper and lower limits of integration.