设实数x，y满足x2+2xy-1=0，则x+y的取值范围是____．

设实数x，y满足x²+2xy-1=0，则x+y的取值范围是____．
【正确答案】：(一∞，一1]∪[1，+∞)。解析：由题意得x²+2xy+y²=y²+1≥1，(x+y)²≥1，x+y≥1或x+y≤一1．

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