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If n - 1 is a factor of n3 - kn? + 2n, what is the value of k.

User Berto
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1 Answer

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7 votes

Answer:

k = 3

Explanation:

given n - a is a factor of f(n) then f(a) = 0

here n - 1 is a factor then f(1) = 0

substitute n = 1 into the polynomial and equate to zero, that is

1³ - k + 2 = 0

1 - k + 2 = 0

3 - k = 0 ( subtract 3 from both sides )

- k = - 3 ( multiply both sides by - 1 )

k = 3

User Nitin Midha
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