解不等式方程:x3+2x2-x-2>0.
问题描述:
解不等式方程:x3+2x2-x-2>0.
答
原不等式可化为x3-x+2x2-2>0,可分解因式可得(x-1)(x2+x+1)+2(x+1)(x-1)>0,即(x-1)(x2+x+1+2x+2)>0,即(x-1)(x2+3x+3)>0,∵x2+3x+3=(x+32)2+34>0,∴(x-1)(x2+3x+3)>0可化为x-1>0,...