4x的平方-12x+y的平方+2y+10=0,求2x-y分之2x+y的值
问题描述：
4x的平方-12x+y的平方+2y+10=0,求2x-y分之2x+y的值
答
4x^2-12x+y^2+2y+10=0
4x^2-12x+9+y^2+2y+1=0
(2x-3)^2+(y+1)^2=0
2x-3=0
x=3/2
y+1=0
y=-1
(2x+y)/(2x-y)
=(2x-y+2y)/(2x-y)
=1+2y/(2x-y)
=1+2*(-1)/[2*(3/2)+1]
=1-2/4
=1-1/2
=1/2
答
4x的平方-12x+y的平方+2y+10
=(2x-3)^2+(y+1)^2
=0
2x=3,y=-1
(2x+y)/(2x-y)
=(3-1)/(3+1)
=2/4
=1/2