• 2022-06-08
    设方程\({x^2} + {y^2} + {z^2} = 2Rx\)确定函数\(z=z(x,y)\),则\( { { \partial z} \over {\partial x}}=\)
    A: \( { { \partial z} \over {\partial x}} = { { R +x} \over z}\)
    B: \( { { \partial z} \over {\partial x}} =- { { R +x} \over z}\)
    C: \( { { \partial z} \over {\partial x}} = { { R - x} \over z}\)
    D: \( { { \partial z} \over {\partial x}} =- { { R - x} \over z}\)