化简求值(3x+1)(2x-3)-(6x-5)(x-4),其中x=-2分之1
问题描述：
化简求值(3x+1)(2x-3)-(6x-5)(x-4),其中x=-2分之1
答
(3x加1)(2x-3)-(6x-5)(x-4)
=(6x^2-7x-3)-(6x^2-29x加20)
=12x^2加22x-23
=12*0.25减11减23
=负31
答
(3x+1)(2x-3)-(6x-5)(x-4)
=6x²-7x-3-(6x²-29x+20)
=22x-23
=22*(-1/2)-23
=-34
答
结果-34,太简单了.