根号3/2sin2x-1+cos2x/2-1/2
问题描述:
根号3/2sin2x-1+cos2x/2-1/2
合一公式怎么解?
答
(√3/2)sin2x-1+(1/2)cos2x-1/2
=cos(30)sin2x+sin30cos2x-3/2
=sin(2x+30)-3/2