f(x)=2sin^2x 3cos x 1的值域
问题描述：
f(x)=2sin^2x 3cos x 1的值域
f(x)=2sin^2x+3cos x+1的值域
答
f(x)=2sin^2x+3cos x+1
=-2(cosx-3/4)^2+33/8
f(x)=2sin^2x+3cos x+1的值域是[-2,33/8]