Question

Solve. (x+2)(x-10)(x+1)>0. The solution set is...? Or the solution set is all real numbers or there is no solution?

Answer 1

solve (x+2)(x-10)(x+1)=0

which gives you x=-2,-1,10

pick a number between -infinity,-2
between -2,-1
between -1,10
between 10,infinity

plug those numbers into (x+2)(x-10)(x+1)

for each one that is positive the entire interval between the roots will also be positive

Answer 2

\[x \in \mathbb{R}, (-2,1)\cup(10,\infty)\]