Home/Calculus II/Trigonometric integrals/Strategy for ∫sinmxcosnx dx\int\sin^m x\cos^n x\,dx∫sinmxcosnxdxSection 6.4Strategy for ∫sinmxcosnx dx\int\sin^m x\cos^n x\,dx∫sinmxcosnxdxIf mmm is odd, reserve a factor sinx\sin xsinx and use sin2x=1−cos2x\sin^2x=1-\cos^2xsin2x=1−cos2x; then u=cosxu=\cos xu=cosx.If nnn is odd, reserve a factor cosx\cos xcosx and use cos2x=1−sin2x\cos^2x=1-\sin^2xcos2x=1−sin2x; then u=sinxu=\sin xu=sinx.If both are even, use power-reduction identities.