Question

曲线xy=1在x=1处的切线方程是

Answer 1

xy=1

y=1/x

x=1代入,y=1

y'=-1/x^2

x=1代入

y'=-1

切线为过(1,1),斜率为-1的直线,设其方程为y-1=-(x-1),整理,得

y=-x+2