【数学】已知f(cosx)=cos5x,则f(sinx)=求详解

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/09 00:09:37

【数学】已知f(cosx)=cos5x,则f(sinx)=求详解
【数学】已知f(cosx)=cos5x,则f(sinx)=
求详解

【数学】已知f(cosx)=cos5x,则f(sinx)=求详解
因为sinx=cos(90-x)
故f(sinx)=f[cos(90-x)]=cos5(90-x)=cos(450-5x)=cos(90-5x)=sin5x

已知f(cosx)=cos5x,则
f(sinx)=f(cos(π/2-x))=cos(5π/2-5x))=sin5x

f(sinx)
=f(cos(π/2-x))
=cos[5(π/2-x)]
=cos(5π/2-5x)
=cos(2π+π/2-5x)
=cos(π/2-5x)
=sin5x
求采纳啊~·/(ㄒoㄒ)/~~

已知f(cosx)=cos5x,求f(sinx)
f(sinx)
=f(cos(π/2-x))
=cos[5(π/2-x)]
=cos(5π/2-5x)
=cos(2π+π/2-5x)
=cos(π/2-5x)
=sin5x