将2sinα-2sin（α-π/3）化为Asin（α+β）的形式是
问题描述：
将2sinα-2sin（α-π/3）化为Asin（α+β）的形式是
答
用a
原式=2sina-2(sinacosπ/3-cosasinπ/3)
=2sina-sina+√3cosa
=sina+√3cosa
=2(sina*1/2+cosa*√3/2)
=2(sinacosπ/3+cosasinπ/3)
=2sin(a+π/3)