Evaluate ∫_C F (r) • dr for given F and C by the method that seems most suitable. Remember that if F is a force, the integral gives the work done in the displacement along C. Show details.

F = [x², y²,y²x], C the helix r = [2 cos t, 2 sin t, 3t] from (2, 0, 0) to (-2, 0, 3π)