x^2+y^2+4x+1=0x^2+y^2+2x+2y+1=02y-2x=0y=x2x^2+4x+1=02(x+1)^2=1x1=-1+√2/2 y1=-1+√2/2x2=-1-√2/2 y2=-1-√2/2d^2=(x1-x2)^2+(y1-y2)^2=2*2=4 r^2=1O'x=(x1+x2)/2=-1O'y=(y1+y2)/2=-1(x+1)^2+(y+1)^2=1
楼上白痴....... 两圆公式相减即可