How can the following two identities be verified?
1. (cos^2y)/(1-siny)=1+siny
2. sin^2a-sin^4a=cos^2a-cos^4a
Thanks!
change cos^2a to 1-sin^2a=(1-sina)(1+sina)
Thank you. I figured out the first one with your help, but I'm still stuck on the second. Any tips?