Evaluate
so by the double angle
this I understand but it shows it go further to
This is where it starts to lose me.
okay so
if true, then is true? That is the way my text book makes it seem
it skips over this step
then inputing that back in
I get
The work the book shows then gets a bit confusing from here (I am working on reviewing key trig components so please bear with me, the book is not always very clear.)