What is the integral of cos^(2)3x dx? Calculus Introduction to Integration Integrals of Trigonometric Functions 1 Answer Lucy Apr 14, 2018 1/2(1/6sin6x +x) +c Explanation: int (cos3x)^2 dx =int 1/2(cos6x +1) dx =1/2intcos 6x+1 dx =1/2(1/6sin6x +x) +c Answer link Related questions How do I evaluate the indefinite integral intsin^3(x)*cos^2(x)dx ? How do I evaluate the indefinite integral intsin^6(x)*cos^3(x)dx ? How do I evaluate the indefinite integral intcos^5(x)dx ? How do I evaluate the indefinite integral intsin^2(2t)dt ? How do I evaluate the indefinite integral int(1+cos(x))^2dx ? How do I evaluate the indefinite integral intsec^2(x)*tan(x)dx ? How do I evaluate the indefinite integral intcot^5(x)*sin^4(x)dx ? How do I evaluate the indefinite integral inttan^2(x)dx ? How do I evaluate the indefinite integral int(tan^2(x)+tan^4(x))^2dx ? How do I evaluate the indefinite integral intx*sin(x)*tan(x)dx ? See all questions in Integrals of Trigonometric Functions Impact of this question 63783 views around the world You can reuse this answer Creative Commons License