当前位置: > [2/xy/(1/x+1/y)2+(x2+y2)/(x2+2xy+y2)]*2x/(x-y)...
题目
[2/xy/(1/x+1/y)2+(x2+y2)/(x2+2xy+y2)]*2x/(x-y)

提问时间:2020-12-14

答案
[2/xy/(1/x+1/y)²+(x²+y²)/(x²+2xy+y²)]*2x/(x-y)
=[2/xy/(x+y)²/x²y²+(x²+y²)/(x+y)²]*2x/(x-y)
=[2xy/(x+y)²+(x²+y²)/(x+y)²]*2x/(x-y)
=[(2xy+x²+y²)/(x+y)²]*2x/(x-y)
=(x+y)²/(x+y)²*2x/(x-y)
=2x/(x-y)
举一反三
已知函数f(x)=x,g(x)=alnx,a∈R.若曲线y=f(x)与曲线y=g(x)相交,且在交点处有相同的切线,求a的值和该切线方程.
我想写一篇关于奥巴马的演讲的文章,写哪一篇好呢?为什么好
奥巴马演讲不用看稿子.为什么中国领导演讲要看?
想找英语初三上学期的首字母填空练习……
英语翻译
版权所有 CopyRight © 2012-2019 超级试练试题库 All Rights Reserved.