∫（t-sint）^2sintdt =∫(t^2sint+sint^2sint-2tsint^2)dt=∫t^2sintdt+∫(1-cost^2)sintdt-2∫tsint^2dt=-∫t^2dcost-∫(1-cost^2)dcost-∫t*(1-cos2t)dt=-t^2cost+∫2costdt-cost+cost^3/3-t^2/2+∫tdsin2t=-t^2c...