题目

5.已知函数z=arcsin(x+2y)，则(partial^2z)/(partial xpartial y)=（）。A. (2x+4y)/([1-(x+2y)^2)]^((3)/(2))B. -(2x+4y)/([1-(x+2y)^2)]^((3)/(2))C. (x+2y)/([1-(x+2y)^2)]^((3)/(2))D. -(x+2y)/([1-(x+2y)^2)]^((3)/(2))

5.已知函数$z=\arcsin(x+2y)$，则$\frac{\partial^{2}z}{\partial x\partial y}=$（）。

A. $\frac{2x+4y}{[1-(x+2y)^{2}]^{\frac{3}{2}}}$

B. $-\frac{2x+4y}{[1-(x+2y)^{2}]^{\frac{3}{2}}}$

C. $\frac{x+2y}{[1-(x+2y)^{2}]^{\frac{3}{2}}}$

D. $-\frac{x+2y}{[1-(x+2y)^{2}]^{\frac{3}{2}}}$

题目解答

A. $\frac{2x+4y}{[1-(x+2y)^{2}]^{\frac{3}{2}}}$