简单啊(x-1)(x+2)=3(x+2)。移项得：(x-1)(x+2)-3(x+2)=0,提取公因式得(x+2)（x-4)=0,所以x=-2 或。x=4
(x-1)(x+2)=3(x+2)(x-1)(x+2)-3(x+2)=0(x+2)(x-1-3)=0x+2=0,或x-4=0x1=-2, x2=4
