设函数y=f(x)由方程xy+2lnx=y4所确定,则曲线y=f(x)在点(1,1)处的法线方程为________.

admin2021-10-18  35

问题 设函数y=f(x)由方程xy+2lnx=y4所确定,则曲线y=f(x)在点(1,1)处的法线方程为________.

选项

答案y=-x+2

解析 xy+2lnx=y4两边对x求导得y+xdy/dx+2/x=4y3dy/dx,将x=1,y=1代入上式得dy/dx|x=1=1,故曲线y=f(x)在点(1,1)处的法线为y-1=-(x-1),即y=-x+2.
转载请注明原文地址:https://kaotiyun.com/show/gAy4777K
0

最新回复(0)