来自李炳成的问题
求导函数:已知函数f(x)=2cos^2(3x-π/6)则函数f(x)在x=π/12处的导数fˊ(π/12)=?
求导函数:已知函数f(x)=2cos^2(3x-π/6)则函数f(x)在x=π/12处的导数fˊ(π/12)=?
1回答
2020-05-21 01:04
求导函数:已知函数f(x)=2cos^2(3x-π/6)则函数f(x)在x=π/12处的导数fˊ(π/12)=?
求导函数:已知函数f(x)=2cos^2(3x-π/6)则函数f(x)在x=π/12处的导数fˊ(π/12)=?
先求导,fˊ(x)=-12cos(3x-π/6)sin(3x-π/6)=-6sin(6x-π/3)
带入数值:fˊ(π/12)=-6sin(π/2-π/3)=-3