已知实数y.x满足(X²+y²)(x²+y²-1)=2试求x²+y²的值
问题描述:
已知实数y.x满足(X²+y²)(x²+y²-1)=2试求x²+y²的值
答
(X²+y²)(x²+y²-1)=2(x²+y²)²-(x²+y²)-2=0(x²+y²-2)(x²+y²+1)=0x²+y²=2或x²+y²=-1x²+y²恒大于等于0x²+y²...