用换元法因式分解 (3x²+24x+7)(2x²+16x+15)+14
问题描述：
用换元法因式分解 (3x²+24x+7)(2x²+16x+15)+14
答
(3（x²+8x+5）-8)(2（x²+8x+5）+5)+14=（3t-8)(2t+5)+14=6t^2-t-40+14=6t^2-t+26=(t+2)(6t-13)=(x^2+8x+5+2)(6x^2+48x+30-13)=(x^2+8x+7)(6x^2+48x+17)=(x+1)(x+7)(6x^2+48x+17)