x^2-y^2=6 x+y=3

来源：百度知道编辑：UC知道时间：2024/04/30 05:58:10

1x^2-y^2=6 x+y=3 求x.y值
2.x^2-y^2=4 (x-y)^2*(x+y)^2=?

x=5/2 y=1/2
(x-y)^2*(x+y)^2=(x^2-y^2)^2= 16

1,
1x^2-y^2=6 (1)
x+y=3 (2)
解:由2式得y=3-x
带入1式得6x=15,得x=5/2,把此结果带入2式得y=1/2

2,把x=5/2,y=1/2带入x^2-y^2=4 (x-y)^2*(x+y)^2得
x^2-y^2=4 (x-y)^2*(x+y)^2=16

1

原式=(x+y)(x-y)=6
因为
x+y=3
所以
x-y=2
所以
x=2.5
y=0.5

2.
原式1=(x+y)(x-y)=4
原式2=(x+y)(x-y)(x+y)(x-y)
=4*4
=16