SOLUTION: find the domain of the rational expression f(x)=1-4x over x^2-2x-15

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Question 459912: find the domain of the rational expression
f(x)=1-4x over x^2-2x-15
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the domain of the rational expression
f(x)=1-4x over x^2-2x-15
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Factor:
f(x) = -(4x-1)/[(x-7)(x+5)]
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The denominator cannot be zero
X cannot be 7 or -5
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Domain: All Real Numbers except x = 7 and x = -5.
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cheers,
Stan H.
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