What is the integral of 1/(cos x)^2? Calculus Introduction to Integration Integrals of Trigonometric Functions 1 Answer mason m Mar 17, 2016 tanx+C Explanation: Note that 1/cosx=secx. Thus, int1/cos^2xdx=intsec^2xdx. This is a common integral: intsec^2xdx=tanx+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 1472 views around the world You can reuse this answer Creative Commons License