问题
填空题
分解因式:x2-y2+3x-y+2=______.
答案
x2-y2+3x-y+2 (x2-y2)+(x+y)+(2x-2y+2)
=(x+y)(x-y)+(x+y)+2(x-y+1)
=(x+y)(x-y+1)+2(x-y+1)
=(x-y+1)(x+y+2);
故答案为(x+y+2)(x-y+1).
分解因式:x2-y2+3x-y+2=______.
x2-y2+3x-y+2 (x2-y2)+(x+y)+(2x-2y+2)
=(x+y)(x-y)+(x+y)+2(x-y+1)
=(x+y)(x-y+1)+2(x-y+1)
=(x-y+1)(x+y+2);
故答案为(x+y+2)(x-y+1).