Question 887991: The values of x that make f(x)= (x-7)(3x+1)(x+4) negative are (- infinity,-4)U(7,infinity)
true or false?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! The values of x that make f(x)= (x-7)(3x+1)(x+4) negative are (- infinity,-4)U(7,infinity)
true or false?
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Draw a number line.
Plot x = -4, x = -1/3, x = 7
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Test a value in each of the intervals for
(x-7)(3x+1)(x+4) < 0
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If x = -10, you get:: -*-*- < 0 which is true
If x = -3, you get:: -*-*+ < 0 which is false
If x = 0, you get:: -*+*+ < 0 which is true
If x = 10, you get:: +*+*+ < 0 which is false
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Ans:: false
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Cheers,
Stan H.
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