解：原式=ax²-bx²+2ax+a+b=(ax²+2ax+a)-(bx²-b)=a(x²+2x+1)-b(x²-1)=a(x+1)²-b(x+1)(x-1)=(x+1)[a(x+1)-b(x-1)]=(x+1)(ax+a-bx+b)
