p+b+r=9,p/(x^2-yz)=b/(y^2-yz)=r/(z^2-xy),求(px+by+rz)/(x+y+z)的值?

分类: 作业答案 • 2022-01-12 12:28:57

问题描述：

答

p/(x^2-yz)=b/(y^2-xz)=r/(z^2-xy)=k
p=k(x^2-yz)
b=k(y^2-xz)
r=k(z^2-xy)
(px+by+rz)/(x+y+z)
=k(x^2-yz)+k(y^2-xz)+k(z^2-xy)
=p+b+r
=9