5、6、7、8题求大神帮忙解答 最好有详细解题化简过程,微积分还是学不会啊

2025-05-03 20:55:03
推荐回答(1个)
回答(1):

u=(x+y)/(1-xy)
z'x=u'x/(1+u²)
=(1-xy-(x+y)(-y))/(1-xy)²(1+u²)
=(1+y²)/((1-xy)²+(x+y)²)
z'y=u'y/(1+u²)
=(1-xy-(x+y)(-x))/(1-xy)²(1+u²)
=(1+x²)/((1-xy)²+(x+y)²)