题目
6.(填空题，17分) 设z=(y)/(x)，则dz=____；dz|_((2,1))=____；dz|_((2,1))_(Delta x=0.1,Delta y=-0.2)=____；Delta z|_((2,1))_(Delta x=0.1,Delta y=-0.2)=____. 四个空依次为(只填写对应字母，如A·B·C等)A. (1)/(x^2)(ydx+xdy)B. (1)/(x^2)(xdy-ydx)C. (1)/(x^2)(ydy-xdx)D. (1)/(4)dx+(1)/(2)dyE. -(1)/(2)dx+(1)/(4)dyF. -(1)/(4)dx+(1)/(2)dyG. -0.1H. -0.075M. 0.125N. (5)/(42)Q. (1)/(14)
6.(填空题，17分) 设$z=\frac{y}{x}$，则dz=____；$dz|_{(2,1)}$=____；$dz|_{(2,1)}_{\Delta x=0.1,\Delta y=-0.2}$=____；$\Delta z|_{(2,1)}_{\Delta x=0.1,\Delta y=-0.2}$=____. 四个空依次为(只填写对应字母，如A·B·C等)
A. $\frac{1}{x^{2}}(ydx+xdy)$
B. $\frac{1}{x^{2}}(xdy-ydx)$
C. $\frac{1}{x^{2}}(ydy-xdx)$
D. $\frac{1}{4}dx+\frac{1}{2}dy$
E. $-\frac{1}{2}dx+\frac{1}{4}dy$
F. $-\frac{1}{4}dx+\frac{1}{2}dy$
G. -0.1
H. -0.075
M. 0.125
N. $\frac{5}{42}$
Q. $\frac{1}{14}$
题目解答
答案
BFGN
B. $\frac{1}{x^{2}}(xdy-ydx)$
F. $-\frac{1}{4}dx+\frac{1}{2}dy$
G. -0.1
N. $\frac{5}{42}$
B. $\frac{1}{x^{2}}(xdy-ydx)$
F. $-\frac{1}{4}dx+\frac{1}{2}dy$
G. -0.1
N. $\frac{5}{42}$