What is how to find inflection points?

Inflection points are points on a curve where the concavity changes. Here's how to find them:

  1. Find the Second Derivative: Calculate the second derivative, often denoted as f''(x), of the function f(x). This requires you to first find the <a href="https://www.wikiwhat.page/kavramlar/first%20derivative" >first derivative</a>, f'(x).

  2. Set the Second Derivative to Zero: Set f''(x) = 0 and solve for x. The solutions are potential inflection points. Also, check where f''(x) is undefined, as these points could also be inflection points.

  3. Test for Change in Concavity: For each potential inflection point c, test the concavity of f(x) on either side of c. You can do this by picking test values slightly less than and slightly greater than c and plugging them into f''(x).

    • If f''(x) > 0, the function is concave up.
    • If f''(x) < 0, the function is concave down.
  4. Confirm Inflection Point: If the concavity changes at c (i.e., f''(x) changes sign from positive to negative or vice-versa), then the point (c, f(c)) is an inflection point. If the concavity does not change, then (c, f(c)) is not an inflection point, even if f''(c) = 0.

Important Considerations:

  • The <a href="https://www.wikiwhat.page/kavramlar/concavity" >concavity</a> test is crucial. Just because the second derivative is zero doesn't guarantee an inflection point.
  • Undefined points in the second derivative should also be checked for concavity changes.