Question 249088: hello
I do not have an exact idea on how to solve this problem below
(x+2)(x-14)(x+1)>0
There will either be a solution set for {x| }
or it will be all real numbers or finally, no solution???
I got as far as multiplying them threw the distributive process. Dont know if this was necessary or not..???
x3rd power -11x2nd power-40x-28 > 0
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! I do not have an exact idea on how to solve this problem below
(x+2)(x-14)(x+1)>0
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1st: Since the left side cannot be zero
x cannot be -2,14,or -1
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2nd: Draw a number line and mark -2,-1,14 on it.
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3rd: That breaks the line up into 4 intervals.
Choose a check point in each interval to see where
the solutions for the INEQUALITY are.
Test each check point in (x+2)(x-14)(x+1)>0
Note: You only need to check the sign of the answer because you
are comparing the value to zero.
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Checking:
If x = -3, you get -*-*- > 0 ; false, so no solutions in (-inf,-2)
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If x = -3/2, you get +*-*- > 0 ; true, so solutions in (-2,-1)
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If x = 13, you get +*-*+ > 0 ; false, so no solutions in (-1,14)
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If x = 15, you get +*+*+ > 0 ; true, so solutions in (14,+inf)
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Final Answer: (-2,-1)U(14,+inf)
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Cheers,
Stan H.
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