1.已知正数x,y满足x2-y2=2xy,求(x-y)/(x+y)的值2.若x2+xy-2y2=0则(x2+3xy-2y2)/x2-2y2)=_________3.先化简,后求值:(3-x)/(x-2)除以(x+2-2/(x-2)),其中x=2√2
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![1.已知正数x,y满足x2-y2=2xy,求(x-y)/(x+y)的值2.若x2+xy-2y2=0则(x2+3xy-2y2)/x2-2y2)=_________3.先化简,后求值:(3-x)/(x-2)除以(x+2-2/(x-2)),其中x=2√2](/uploads/image/z/697797-45-7.jpg?t=1.%E5%B7%B2%E7%9F%A5%E6%AD%A3%E6%95%B0x%2Cy%E6%BB%A1%E8%B6%B3x2-y2%3D2xy%2C%E6%B1%82%28x-y%29%2F%28x%2By%29%E7%9A%84%E5%80%BC2.%E8%8B%A5x2%2Bxy-2y2%3D0%E5%88%99%28x2%2B3xy-2y2%29%2Fx2-2y2%29%3D_________3.%E5%85%88%E5%8C%96%E7%AE%80%2C%E5%90%8E%E6%B1%82%E5%80%BC%EF%BC%9A%283-x%29%2F%28x-2%29%E9%99%A4%E4%BB%A5%EF%BC%88x%2B2-2%2F%28x-2%29%EF%BC%89%2C%E5%85%B6%E4%B8%ADx%3D2%E2%88%9A2%26%23160%3B)
1.已知正数x,y满足x2-y2=2xy,求(x-y)/(x+y)的值2.若x2+xy-2y2=0则(x2+3xy-2y2)/x2-2y2)=_________3.先化简,后求值:(3-x)/(x-2)除以(x+2-2/(x-2)),其中x=2√2
1.已知正数x,y满足x2-y2=2xy,求(x-y)/(x+y)的值
2.若x2+xy-2y2=0则(x2+3xy-2y2)/x2-2y2)=_________
3.先化简,后求值:(3-x)/(x-2)除以(x+2-2/(x-2)),其中x=2√2
1.已知正数x,y满足x2-y2=2xy,求(x-y)/(x+y)的值2.若x2+xy-2y2=0则(x2+3xy-2y2)/x2-2y2)=_________3.先化简,后求值:(3-x)/(x-2)除以(x+2-2/(x-2)),其中x=2√2
1.x²-y²=(x+y)(x-y)=2xy...1
x²-y²-2xy=0
x²-2xy+y²=2y²
(x-y)²=2y².2
2/1=(x-y)/(x+y)=2y²/2xy=1/x
2.x²+xy-2y²=0
x²+3xy-2y²=2xy.1
x²+xy-2y²=0
x²-2y²=-xy.2
1/2=2xy/(-xy)=-2
3.3-x
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x-2 3-x 3-x 3-2√2
---------- =------ = ----- = -------
2 x²-4-2 x²-6 2
x+2- ——
x-2