把式子x2-y2+5x+3y+4分解因式的结果是 _ .
问题描述:
把式子x2-y2+5x+3y+4分解因式的结果是 ___ .
答
x2-y2+5x+3y+4
=(x2+4x+4)-(y2-4y+4)+x-y+4
=(x+2)2-(y-2)2+x-y+4
=(x+y)(x-y+4)+(x-y+4)
=(x-y+4)(x+y+1).
故答案是:(x-y+4)(x+y+1).