圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )A.(x+3)^2+(y-2)^2=1/2B.(x-3)^2+(y+2)^2=1/2C.(x+3)^2+(y-2)^2=2D.(x-3)^2+(y+2)^2=2网上的我有些看不大懂额
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![圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )A.(x+3)^2+(y-2)^2=1/2B.(x-3)^2+(y+2)^2=1/2C.(x+3)^2+(y-2)^2=2D.(x-3)^2+(y+2)^2=2网上的我有些看不大懂额](/uploads/image/z/560822-14-2.jpg?t=%E5%9C%86x%5E2%2By%5E2-2x-1%3D0%E5%85%B3%E4%BA%8E%E7%9B%B4%E7%BA%BF2x-y%2B3%3D0%E5%AF%B9%E7%A7%B0%E7%9A%84%E5%9C%86%E7%9A%84%E6%96%B9%E7%A8%8B%E6%98%AF%EF%BC%88+%EF%BC%89%E5%9C%86x%5E2%2By%5E2-2x-1%3D0%E5%85%B3%E4%BA%8E%E7%9B%B4%E7%BA%BF2x-y%2B3%3D0%E5%AF%B9%E7%A7%B0%E7%9A%84%E5%9C%86%E7%9A%84%E6%96%B9%E7%A8%8B%E6%98%AF%EF%BC%88+%EF%BC%89A.%28x%2B3%29%5E2%2B%28y-2%29%5E2%3D1%2F2B.%28x-3%29%5E2%2B%28y%2B2%29%5E2%3D1%2F2C.%28x%2B3%29%5E2%2B%28y-2%29%5E2%3D2D.%28x-3%29%5E2%2B%28y%2B2%29%5E2%3D2%E7%BD%91%E4%B8%8A%E7%9A%84%E6%88%91%E6%9C%89%E4%BA%9B%E7%9C%8B%E4%B8%8D%E5%A4%A7%E6%87%82%E9%A2%9D)
圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )A.(x+3)^2+(y-2)^2=1/2B.(x-3)^2+(y+2)^2=1/2C.(x+3)^2+(y-2)^2=2D.(x-3)^2+(y+2)^2=2网上的我有些看不大懂额
圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )
圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )
A.(x+3)^2+(y-2)^2=1/2
B.(x-3)^2+(y+2)^2=1/2
C.(x+3)^2+(y-2)^2=2
D.(x-3)^2+(y+2)^2=2
网上的我有些看不大懂额
圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )圆x^2+y^2-2x-1=0关于直线2x-y+3=0对称的圆的方程是( )A.(x+3)^2+(y-2)^2=1/2B.(x-3)^2+(y+2)^2=1/2C.(x+3)^2+(y-2)^2=2D.(x-3)^2+(y+2)^2=2网上的我有些看不大懂额
x^2+y^2-2x-1=0的变形是y^2+(x-1)^2=2,所以这个圆的圆心是(1,0),半径是必须在中线根号2,对称的圆至少要和原来的圆半径相同,所以排除A,B,再看C,D,C的圆心是(-3,2),D的圆心是(3,-2).若想成为题目中所谈到圆的对称圆,这个圆的圆心和题目中圆的圆心的连线的中点必须在直线2x-y+3=o上,C中的圆与题中圆的中点是(-1,1),代入直线,可看出在直线上,D中的圆与题中圆的中点是(2,-1),代入直线,可看出不在直线上.所以答案选C.