SOLUTION: Please solve and explain 2x^2-6>11

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Question 1021512: Please solve and explain 2x^2-6>11
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
2x%5E2-17%3E0
So now you want to graph the function and look for the region where the function is greater than zero (above the x-axis).
You can solve for when the function equals zero first.
2x%5E2=17
x%5E2=%2817%2F2%29
x=0+%2B-+sqrt%2817%2F2%29%7D%7D%0D%0A%7B%7B%7Bx=0+%2B-+sqrt%2834%29%2F2%29
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So now choose a point in between the zeros and check whether the function is above or below the x-axis at that point.
x=0 is convenient.
2%280%29%5E2-6%3E11
-6%3E11
False, so in between the zeros the function is not greater than zero.
So the other regions are the where the function is greater than zero.
(-infinity,-sqrt%2834%29%2F2)U(sqrt%2834%29%2F2,infinity)
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