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f(x) = x^2 + x − 6 Determine the coordinates of any maximum or minimum, and intervals of increase and decrease. And can you please explain how you got your answer.

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Answer:

To find the coordinates of any maximum or minimum and the intervals of increase and decrease for the function f(x) = x^2 + x - 6, we need to analyze its first and second derivatives.

Let's go step by step:

Find the first derivative:

f'(x) = 2x + 1

Set the first derivative equal to zero to find critical points:

critical points: 2x + 1 = 0

critical points: 2x + 1 = 0 2x = -1

critical points: 2x + 1 = 0 2x = -1 x = -1/2

Determine the second derivative:

f''(x) = 2

f''(x) = 2Since the second derivative is a constant (2), we can conclude that the function is concave up for all values of x. This means that the critical point we found in step 2 is a minimum.

Determine the coordinates of the minimum:

To find the y-coordinate of the minimum, substitute the x-coordinate (-1/2) into the original function: f(-1/2) = (-1/2)^2 - 1/2 - 6 f(-1/2) = 1/4 - 1/2 - 6 f(-1/2) = -24/4 f(-1/2) = -6

So, the coordinates of the minimum are (-1/2, -6).

Analyze the intervals of increase and decrease:

Since the function has a minimum, it increases before the minimum and decreases after the minimum.

Interval of Increase:

(-∞, -1/2)

Interval of Decrease:

(-1/2, ∞)

To summarize:

  • The coordinates of the minimum are (-1/2, -6).
  • The function increases on the interval (-∞, -1/2).
  • The function decreases on the interval (-1/2, ∞).
User Andrey D
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