How do you integrate #(8x)/(4x^2+1)#? Calculus Introduction to Integration Integrals of Rational Functions 1 Answer Bill K. Aug 10, 2015 #int (8x)/(4x^2+1)\ dx=ln(4x^2+1)+C# Explanation: Do a substitution: let #u=4x^2+1# so #du = 8x\ dx#. Therefore, #int (8x)/(4x^2+1)\ dx=int 1/u\ du=ln|u|+C# #=ln|4x^2+1|+C#. Since #4x^2+1 geq 1 > 0# for all #x in RR#, we can get rid of the absolute value signs and write: #int (8x)/(4x^2+1)\ dx=ln(4x^2+1)+C# Answer link Related questions How do you integrate #(x+1)/(x^2+2x+1)#? How do you integrate #x/(1+x^4)#? How do you integrate #dx / (2sqrt(x) + 2x#? What is the integration of #1/x#? How do you integrate #(1+x)/(1-x)#? How do you integrate #(2x^3-3x^2+x+1)/(-2x+1)#? How do you find integral of #((secxtanx)/(secx-1))dx#? How do you integrate #(6x^5 -2x^4 + 3x^3 + x^2 - x-2)/x^3#? How do you integrate #((4x^2-1)^2)/x^3dx #? How do you integrate #(x+3) / sqrt(x) dx#? See all questions in Integrals of Rational Functions Impact of this question 4500 views around the world You can reuse this answer Creative Commons License