Question

Solution set of inequality $\frac{(x^2-1)(x+2)}{(1-x)}\ge 0$ is

• A. $[-2,0)$
• B. $[-2,1)$
• C. $[-2,-1]$
• D. $[-1,1)\cup (1,\infty )$

Answer 1

Answer: (C)

$[-2,-1]$

inequality $\frac{(x^2-1)(x+2)}{(1-x)}\ge 0$ has critical points where function is zero or not defined is $-1,1,-2$
drwaing points on line and checking for the sign change, gives sign of function change at $-2$ and $-1$ so solution set is $[-2,-1]$.