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Give f(x) = 3x^3+kx-13, and x-1 is a factor of f(x), then what is the value of k?

User Michael IV
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Answer: If x-1 is a factor of f(x) = 3x^3+kx-13, then f(x) can be written as (x-1)g(x) for some polynomial g(x). This means that f(1) = 0.

We can substitute x = 1 into f(x) to get f(1) = 3(1)^3 + k(1) - 13 = 3 + k - 13 = 0.

Therefore k - 10 = 0, so k = 10

So the value of k is 10.

Explanation:

User Penleychan
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