Integration By Parts: Need help with a step.... Evaluate the integral: [tex]\int[/tex] ln(2x + 1)dx I worked it out up until: Xln(2x + 1) - [tex]\int[/tex] 2x/(2x + 1) dx Then the next step throws me off. I attached a scan from the solutions manual and circled the part that confused me. Could somebody explain how we went from "2x/(2x + 1)" to "[(2x + 1) - 1]/(2x + 1)"? I'm sure it's a simple arithmetic step I'm overlooking, which is why I'm reviewing a few weeks before Calc. 2.