



 
Hi Chris, When I see this question I realize that I need to express cos(2x) in terms of sin(x) and cos(x). I know that
But the left side has only sin^{2}(x) and no cosines so in the expression for cos(2x) above I can use the act that
to eliminate the cosine term. So here is how my solution starts
Can you complete it? Harley  


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences. 