函数y=sinx+cosx,x属于[0,pai]的值域是

问题描述:

函数y=sinx+cosx,x属于[0,pai]的值域是

y=sinx+cosx
=√2sin(x+π/4)
因x∈[0,π],则x+π/4∈[π/4,5π/4],则sin(x+π/4)∈[-√2/2,1],
则y∈[-1,√2]