|x²-2x|=a²+1
(1)x²-2x=a²+1
(x-1)²=a²+2
x-1=±根号(a²+2)
x=1±根号(a²+2)
(2)x²-2x=-a²-1
(x-1)²=-a²0)的解的个数是2个