66800167
幼苗
共回答了16个问题采纳率:87.5% 举报
f=sqrt[(x0-x)^2+(y0-y)^2+(z0-z)^2]
df/dx=1/2*{1/sqrt[(x0-x)^2+(y0-y)^2+(z0-z)^2]}*2(x0-x)*-1
=(x-x0)/sqrt[(x0-x)^2+(y0-y)^2+(z0-z)^2]
同理
df/dy=(y-y0)/sqrt[(x0-x)^2+(y0-y)^2+(z0-z)^2]
df/dz=(z-z0)/sqrt[(x0-x)^2+(y0-y)^2+(z0-z)^2]
1年前
9