Did you make a mistake when you multiplied the 3 terms by the 4 terms?
And I also do not understand what all that stuff in the beginning is?
As in proving trig identities, here it is better to check first if the probvlem identity is true for a numerical substitution.Originally Posted by DenMac21
Try x=0 and y=2.
You get the LHS to be 13/4, while the RHS to be 7/2.
LHS <> RHS, hence, not an identity.
So no need to crack cranium for those x's and y's.