(x+2)(x+3)(x+8)(x+12)-4x^2初三数学.因式分解.学霸请进!
问题描述:
(x+2)(x+3)(x+8)(x+12)-4x^2
初三数学.因式分解.学霸请进!
答
原式=[(x+2)(x+12)][(x+3)(x+8)]-4x²
=[(x²+24)+14x][(x²+24)+11x]-4x²
=(x²+24)²+25x(x²+24)+154x²-4x²
=(x²+24)²+25x(x²+24)+150x²
=(x²+24+10x)(x²+24+15x)
=(x+4)(x+6)(x²+15x+24)