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If 4 is a zero of f(x) = 3x^3+kx-2 what is k

1 Answer

6 votes

Answer:

K = -47.5

Step-by-step explanation:

The zero of an equation is a number that when substituted in the equation gives the result zero

We are given that:

4 is a zero of f(x) = 3x³ + kx - 2

This means that:

When we substitute x = 4 in f(x) the result will be zero

Therefore:

3(4)³ + k(4) - 2 = 0

Now, we simply solve for K as follows:

3(4)³ + k(4) - 2 = 0

3(64) + 4k - 2 = 0

192 + 4k - 2 = 0

190 + 4k = 0

4k = -190

k = -47.5

Hope this helps :)

User Andrei Arsenin
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