f(sin x)=cos2X 那么f(cos x)=

来源：学生作业学帮网编辑：学帮网时间：2024/05/15 14:55:27

f(cosx)
=f[sin(π/2-x)]
=cos2(π/2-x)
=cos(π-2x)
=-cos2x

f(sin x)=cos 2X=1-2(sinx)^2
f(x)=1-2x^2
f(cosx)=1-2(cos x)^2