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1.分解因式x^2-y^2+y-4/12.已知x^2+^y^2-8x-10y+41=0,求x/y-y/x的值.

题目详情
1.分解因式
x^2-y^2+y-4/1
2.已知x^2+^y^2-8x-10y+41=0,求x/y-y/x的值.
▼优质解答
答案和解析
1.分解因式
x^2-y^2+y-1/4
= x^2-(y^2-y+1/4)
=x^2-(y-1/2)^2
=(x+y-1/2)(x-y+1/2)
2.已知x^2+^y^2-8x-10y+41=0,求x/y-y/x的值.
x^2+y^2-8x-10y+41=0
x^2-8x+16+y^2-10y+25=0
(x-4)^2+(y-5)^2=0
所以
x=4,
y=5
x/y-y/x=4/5-5/4=0.8-1.25=-0.45