Grade 11Trigonometry
if alpha and beta are the solutions of a cos theta +b sin theta=c then show that cos (alpha - beta)=2c*c-(a*a+b*b)+a*a+b*b
if alpha and beta are the solutions of a cos theta +b sin theta=c then show that cos (alpha - beta)=2c*c-(a*a+b*b)+a*a+b*b
