化简y=cos^2(x/2)+sin^2(x/2)+sinx为y=Asin(Bx+C)

问题描述:

化简y=cos^2(x/2)+sin^2(x/2)+sinx为y=Asin(Bx+C)

是y=cos^2(x/2)-sin^2(x/2)+sinx
=sinx+cosx
=√2(√2/2*sinx+√2/2cosx)
=√2(sinxcosπ/4+cosxsinπ/4)
=√2sin(x+π/4)