解不等式:(x-1)(x-2)(x-3)(x-4)>120

问题描述:

解不等式:(x-1)(x-2)(x-3)(x-4)>120

=[(X-1)(X-4)][(X-2)(X-3)]-120=[(X²-5X)+4][(X²-5X)+6]-120=(X²-5X)²+10(X²-5X)+24-120=(X²-5X)²+10(X²-5X)-96=(X²-5X-6)(X²-5X+16)=(X-6)(X+1)(X²-5X+16)...太给力了,你的回答完美解决了我的问题!