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Given f(x) = 3x^3– 2x + k, and x-2 is a factor of f(x), then what is the value of K

User Bill Fraser
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1 Answer

17 votes
17 votes

Answer:

k = - 20

Explanation:

(x - h) is a factor of f(x), then by the remainder theorem f(a) = 0 , then

substituting x = 2 into f(x) and equating to zero, gives

3(2)³ - 2(2) + k = 0

3(8) - 4 + k = 0

24 - 4 + k = 0

20 + k = 0 ( subtract 20 from both sides )

k = - 20

User Ilo
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