(x^ - 4x+3)(x^+12x+35)+15 .
问题描述:
(x^ - 4x+3)(x^+12x+35)+15 .
指数为二.^是指数.
答
(x^ - 4x+3)(x^+12x+35)+15
=(x-1)(x-3)(x+5)(x+7)+15
=(x^2+4x-5)(x^2+4x-21)+15
=(x^2+4x-5)^2-16(x^2+4x-5)+15
=(x^2+4x-20)(x^2+4x-6)