圆心A(a,0),a>0r=AC=|a-1|弦长是2√2弦心距即A到x-y-1=0距离d=|a-0-1|/√2勾股定理d²+(2√2/2)²=r²(a-1)²/2+2=(a-1)²(a-1)²=4a-1=±2a>0a=3r=|a-1|=2所以(x-3)²+y²=4...