已知x+y=-4,xy=-12,求(x+1/y+1 )+ ( y+1/x+1)的值要写过程啊

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已知x+y=-4,xy=-12,求(x+1/y+1 )+ ( y+1/x+1)的值要写过程啊

已知x+y=-4,xy=-12,求(x+1/y+1 )+ ( y+1/x+1)的值要写过程啊
已知x+y=-4,xy=-12,求(x+1/y+1 )+ ( y+1/x+1)的值
要写过程啊

已知x+y=-4,xy=-12,求(x+1/y+1 )+ ( y+1/x+1)的值要写过程啊
x+y=-4,则(x+y)²=x²+2xy+y²=(-4)²=16
所以x²+y²=16-2xy=16+24=40
(x+1/y+1 )+ ( y+1/x+1)
=(x+1)²/[(x+1)(y+1)]+(y+1)²/[(x+1)(y+1)]
=[(x+1)²+(y+1)²]/[(x+1)(y+1)]
=(x²+y²+2x+2y+2)/(xy+x+y+1)
=(40+2×(-4)+2)/(-12-4+1)
=34/(-15)
=-34/15

x+y=-4,xy=-12,左边除以左边,右边除以右边,得(x+y)/(xy)=1/x+1/y=(-4)/(-12)=1/3,(x+1/y+1 )+ ( y+1/x+1)=x+y+2+1/x+1/y=-4+2+1/3=-5/3