## Idealist 2 years ago f(x)=(x+2)^3-4. The point (-2, -4) is which of the following? A) An absolute maximum B) An absolute minimum C) A critical point but not an extremum D) Not a critical point E) None of these I think the answer is C, am I right?

1. Dido525

Is this a calculs question or have you not learnt any calculus yet?

2. Idealist

A Calculus question and I take this class right now.

3. Dido525

You know to find a maximum or minimum you find the derivative right?

4. Idealist

Yes. But I wonder if C is the right answer. Do you must find the maximum and the minimum for this problem? If so, what to do after finding the derivatives?

5. Dido525

Okay, after you find the derivative, you set it equal to zero and solve for x.

6. Dido525

You substitute a number smaller than and a number bigger than x into the derivative.

7. Dido525

If the derivative changes from a - to a + the function has a local min. If the derivative changes from + to - the function has a local max.

8. Dido525

A critical number is where the value of x you find makes the derivative equal to 0 or makes it undefined.

9. Dido525

Okay I just did all the work out. You are correct :P .

10. Dido525

@Idealist