分母有理化x=2-√3所以x-1<0|x-1|=-(x-1)且18x=2+√3原式=(x-1)²/(x-1)-√(x-1)/x(x-1)=x-1-|x-1|/x(x-1)=x-1+(x-1)/x(x-1)=x-1+1/x=2-√3-1+2+√3=3