求证sin^2x+sin^2y-sin^2x*sin^2y+cos^2x*cos^2y=1
题目
求证sin^2x+sin^2y-sin^2x*sin^2y+cos^2x*cos^2y=1
答案
sin^2x+sin^2y-sin^2x*sin^2y+cos^2x*cos^2y= sin^2x-sin^2x*sin^2y+sin^2y+cos^2x*cos^2y= sin^2x*(1-sin^2y)+sin^2y+cos^2x*cos^2y= sin^2x*cos^2y+sin^2y+cos^2x*cos^2y= sin^2x*cos^2y+cos^2x*cos^2y+sin^2y= co...
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
最新试题
热门考点