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Find all the relative and absolute extrema of the given function on the given domain. (Order your answers from smallest to largest x.)

g(x) = x4 − 4x on [−3, 1]Find all the relative and absolute extrema of the given function on the given domain. (Order your answers from smallest to largest x.)
g(x) = x4 − 4x on [−3, 1]

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Final answer:

To find the relative and absolute extrema of the function g(x) = x^4 - 4x on the domain [-3, 1], we can follow these steps: take the derivative, find critical points, evaluate function at endpoints, compare values to determine extrema. The extrema for this function on the given domain are as follows: absolute maximum at (81, 6561), relative minimum at (-3, 81), and another relative minimum at (1, -3).

Step-by-step explanation:

To find the relative and absolute extrema of the function g(x) = x4 - 4x on the domain [-3, 1], we can follow these steps:

  1. Take the derivative of g(x) to find critical points.
  2. Find the endpoints of the domain and evaluate g(x) at those points.
  3. Compare the values of g(x) at critical points and endpoints to determine the relative and absolute extrema.

Let's proceed with these steps:

  1. Taking the derivative of g(x), we get g'(x) = 4x3 - 4.
  2. Setting g'(x) = 0, we solve 4x3 - 4 = 0 to find the critical points. Simplifying, we get x3 - 1 = 0, which factors as (x-1)(x2 + x + 1) = 0. Consequently, the critical point is x = 1.
  3. The domain [-3, 1] has two endpoints, -3 and 1. Evaluating g(x) at these points, we find g(-3) = 81 and g(1) = -3.
  4. Next, we compare the values of g(x) at the critical point and endpoints. We find that g(1) = -3 is the smallest value, g(81) = 6561 is the largest value, and g(-3) = 81 is another relative minimum.

Therefore, the relative and absolute extrema of the function g(x) = x4 - 4x on the domain [-3, 1] are:

  • Absolute maximum: g(81) = 6561 at x = 81
  • Relative minimum: g(-3) = 81 at x = -3
  • Relative minimum: g(1) = -3 at x = 1
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