已知y2
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已知圆方程X2+Y2=25
已知x、y满足x2+y2+174
已知圆x2+y2=25,求:
2010.09.已知x、y为实数,且(x2+y2)(x2+y2+1)=20,求x2+y2的值
已知(x2+y2)(x2+y2-6)+9=0,求x2+y2的值.
已知(x2+y2)(x2-1+y2)-12=0,求x2+y2的值.
已知x,y为实数,且(x2 +y2)(x2 +y2+2)=3.求x2 +y2的值
已知实数x.y满足(x2+y2)(x2+y2-1)=2,求x2+y2的值
1.已知y1=-x+2,y2=3x+4,当x分别取何值时,y1=y2,y1<y2,y1>y2?
已知x2+4y2+x2y2-6xy+1=0,求 x4-y4/2x-y 乘 2xy-y2/xy-y2 除以(x2+y2/x