u/Electrical-Track7851

Hello everyone,

Im currently in calc 2 hell and this question was on my most recent test. I solved it using way #1 and got it wrong. I went to the professor after class and he showed me it was supposed to be solved like #2.

Can anyone explain why you are supposed to multiply the 2 in first to get (2n+2)! instead of just canceling out the 2(n+1)n! with 2n! to get (n+1).

thanks