Concept:Rewrite the integrand in terms of tanx and sec2x, then apply the standard power rule for integration.Explanation:We are given:I=∫cos−73x⋅sin−711xdxUse the identity sinx=tanx⋅cosx.Then:sin−711x=cos−711x⋅tan−711xMultiplying by cos−73x gives:cos−714x⋅tan−711x=sec2x⋅tan−711xSo the integral becomes:I=∫tan−711x⋅sec2xdxLet u=tanx, so du=sec2xdx.Thus:I=∫u−711du=−74u−74+cSimplify:I=−47tan−74x+cAnswer:−47tan−74x+cHence, the correct option is C.