How do you find the antiderivative of # (cosx)/(x) #? Calculus Introduction to Integration Integrals of Trigonometric Functions 1 Answer A. S. Adikesavan Jun 28, 2016 #ln x-(1/2)sum(-1)^nx^(2n)/(n(2n)!)+C, n=1, 2, 3,...,# #and 0 < x<=1 #. Explanation: #cos x/x = sum((-1)^nx^(2n-1))/(2n)!, n=0, 1, 2, 3, .., #.for non-zero x. #int cos x /x dx= int# #sum((-1)^nx^(2n-1))/(2n)!, n=0, 1, 2, 3, .., #and# 0 < x<=1#. #=ln x-(1/2)sum(-1)^nx^(2n)/(n(2n)!)+C, n=1, 2, 3,..., # #and 0 < x<=1 #. 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 3447 views around the world You can reuse this answer Creative Commons License