SOLUTION: Please provide in interval notation: x3+9x2-108>=0

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Question 851880: Please provide in interval notation: x3+9x2-108>=0
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
factors to %28x-3%29%2A%28x%2B6%29%5E2
so we check the intervals
[-oo, -6]
(+)(-) so negative except at x=-6
[-6, 3]
(-)(+) so negative except at x=-6 and x=3

[3,oo]
(+)(+) positive

solution:
{-6} U [3, oo)