I'm stuck again... I don't know why I am having so much trouble with these. There is clearly something I'm just not seeing.
1 + cos2x = cotx sin2x
I think I need to simplify the right hand side?
This is what I've done, but I'm making a real mess of things....
= cosx sin2x/ sinx
= [cosx (2sinx cosx)] / sinx
And then I'm lost...