How do you integrate #int cos((2x)/3)# from [0, pi/2]? Calculus Introduction to Integration Definite and indefinite integrals 1 Answer Andrea S. Feb 13, 2017 #int_0^(pi/2) cos((2x)/3)dx = 3/2 int_0^(pi/2) cos((2x)/3)d((2x)/3) = 3/2 [sin((2x)/3)]_0^(pi/2) = 3/2( sin (pi/3) -sin 0) = (3sqrt(3))/4# Answer link Related questions What is the difference between definite and indefinite integrals? What is the integral of #ln(7x)#? Is f(x)=x^3 the only possible antiderivative of f(x)=3x^2? If not, why not? How do you find the integral of #x^2-6x+5# from the interval [0,3]? What is a double integral? What is an iterated integral? How do you evaluate the integral #1/(sqrt(49-x^2))# from 0 to #7sqrt(3/2)#? How do you integrate #f(x)=intsin(e^t)dt# between 4 to #x^2#? How do you determine the indefinite integrals? How do you integrate #x^2sqrt(x^(4)+5)#? See all questions in Definite and indefinite integrals Impact of this question 2033 views around the world You can reuse this answer Creative Commons License