(1)先化简,再求值:(3x+1)(x-1)-(3x3+x2-2x)÷x,其中x=-1;
(2)解不等式:(2x-1)2-x(x-1)<3(x+1)(x-1).
网友回答
解:(1)(3x+1)(x-1)-(3x3+x2-2x)÷x
=3x2-2x-1-3x2-x+2
=-3x+1,
当x=-1时,原式=4;
(2)(2x-1)2-x(x-1)<3(x+1)(x-1),
4x2-4x+1-x2+x<3x2-3,
即-3x<-4,
解得:.
解析分析:(1)本题需先根据整式的混和运算顺序和法则分别进行计算,再把x=-1代入即可求出