Question #ea2e9 Calculus Introduction to Integration Definite and indefinite integrals 1 Answer Andrea S. Feb 27, 2017 #int (2x)/e^x dx = -2e^(-x)(x+1)+C# Explanation: Considering that #1/e^x = e^(-x)# we can write the integral as: #int (2x)/e^x dx = 2int xe^(-x)dx# and integrate by parts: #int (2x)/e^x dx = -2int xd(e^(-x)) = -2xe^(-x) +2inte^(-x)dx# #int (2x)/e^x dx = -2xe^(-x) -2e^(-x) +C# #int (2x)/e^x dx = -2e^(-x)(x+1)+C# 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 1052 views around the world You can reuse this answer Creative Commons License