SOLUTION: Factor​ f(x) into linear factors given that k is a zero of​ f(x). f(x)= 4x^3+3x^2-81x+20; k=4

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Factor​ f(x) into linear factors given that k is a zero of​ f(x). f(x)= 4x^3+3x^2-81x+20; k=4       Log On


   

Question 1055882: Factor​ f(x) into linear factors given that k is a zero of​ f(x). f(x)= 4x^3+3x^2-81x+20; k=4

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Factor​ f(x) into linear factors given that k is a zero of​ f(x).
f(x)= 4x^3+3x^2-81x+20; k=4
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4)....4....3....-81....20
......4...19....-5...|..0
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Quotient:: 4x^2 + 19x -5
Factor::
4x^2 +20x -x - 5
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4x(x+5)-(x+5)
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(x+5)(4x-1)
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Ans: f(x) = (x-4)(x+5)(4x-1)
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Cheers,
stan H.
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