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Let f(x) = x³ + kx² + 6. Find the value of h and k so that (x + 1) and (x -2) are factors of f(ˣ).

User Dualmon
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1 Answer

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Final answer:

To find the value of k, we use the given factors (x + 1) and (x - 2) and set them equal to zero to find k. However, since substituting these x-values in the function f(x) = x³ + kx² + 6 yields different k values, there may be an error in the problem statement or factors given.

Step-by-step explanation:

To find the value of k for the function f(x) = x³ + kx² + 6 given that (x + 1) and (x - 2) are factors, we can use polynomial division or factor by grouping. Since these are factors of f(x), we know that f(-1) = 0 and f(2) = 0. By substituting these x-values, we can solve for k.

First, let's use f(-1) = (-1)³ + k(-1)² + 6 = 0:

  • -1 + k + 6 = 0
  • k = -5

Now, let's use f(2) = (2)³ + k(2)² + 6 = 0:

  • 8 + 4k + 6 = 0
  • 4k = -14
  • k = -14/4
  • k = -3.5

However, since we get different values for k, this suggests a mistake in either the problem statement or in the factors provided. If (x + 1) and (x - 2) are indeed factors of f(x), then both calculations should yield the same k value. Please double-check the factors and/or the function given.

User WendiKidd
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