cos(x-π/3)=sin(x+π/6)这两者相等吗?

问题描述:

cos(x-π/3)=sin(x+π/6)这两者相等吗?

∵sin(x+π/6)=sinxcosπ/6+cosxsinπ/6
=(√3/2)sinx+(1/2)cosx,
cos(x-π/3)=cosxcosπ/3+sinxsinπ/3
=(1/2)cosx+(√3/2)sinx.
∴相等.