sinx+cosx=√2sin(x+π/4)
问题描述:
sinx+cosx=√2sin(x+π/4)
说明原因,
最好做一下.
答
sinx+cosx
=√2(cos45°sinx+sin45°cosx)
=√2sin(x+45°)
==√2sin(x+π/4)