Inflection Points and Local Minimums

In summary, the conversation is about finding values for a, b, c, d, e and q, r, s, t, u in two different equations to create specific points of inflection and local minimum and maximum points. The suggested values for q, r, s, t, and u to achieve these points are q = 4, r = 5, s = 3, t = 1, u = 0.
  • #1
carbonsteel
4
0
1. Use the following equations to fill in the missing numbers. The correct addition and subtraction signs have already been entered.

PROBLEM ONE:
f(x) = ax4 + bx3 - cx2 - dx - e

Find values of a,b,c,d, and e so that the function has inflection points at ((v3)/3, -7.5752) and (-(v3)/3, -.647009) and has a local minimum at (1.26255, -11.8696).


PROBLEM TWO:
f(x) = qx4 - rx3 - sx2 +tx + u

Find values of q, r, s, t, and u so that the function has local minimums at (-.398238, -.457621) and (1.20556, -3.46602) also so the function has a local maximum at (.130182, .069458).




2. See above



3. ?

I never took calculus. Need assistance in solving these problems to solve a puzzle. I need to know what the values are for a, b, c, d, e and q, r, s, t, u.

Thank you.
 
Physics news on Phys.org
  • #2
carbonsteel said:
PROBLEM TWO:
f(x) = qx4 - rx3 - sx2 +tx + u

Find values of q, r, s, t, and u so that the function has local minimums at (-.398238, -.457621) and (1.20556, -3.46602) also so the function has a local maximum at (.130182, .069458).

Thank you.

Were you really given those decimals or have you rounded something off?

Try q = 4, r = 5, s = 3, t = 1, u = 0
 

What is an inflection point?

An inflection point is a point on a curve where the concavity of the curve changes. This means that the curve goes from being concave up to concave down, or vice versa.

How do you find inflection points?

To find inflection points, you must first take the second derivative of the function. Then, set the second derivative equal to zero and solve for x. The resulting values of x are the potential inflection points. To confirm if they are inflection points, you can check the concavity of the curve at those points.

What is a local minimum?

A local minimum is a point on a curve where the function has its lowest value within a specific interval. This means that the function is increasing on either side of the point.

How do you determine if a point is a local minimum?

To determine if a point is a local minimum, you must first check if the point is a critical point (where the derivative is equal to zero or undefined). Then, you can use the first or second derivative test to determine if the point is a local minimum. If the derivative changes from negative to positive at the point, it is a local minimum.

What is the relationship between inflection points and local minimums?

An inflection point can also be a local minimum, but this is not always the case. Inflection points occur when the concavity of the curve changes, while local minimums occur when the function has its lowest value within a specific interval. Therefore, an inflection point can be a local minimum if the function also has its lowest value at that point.

Similar threads

  • Calculus and Beyond Homework Help
Replies
5
Views
1K
  • Calculus and Beyond Homework Help
Replies
2
Views
310
  • Calculus and Beyond Homework Help
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
18
Views
1K
  • Calculus and Beyond Homework Help
Replies
11
Views
1K
  • Topology and Analysis
Replies
4
Views
750
  • Calculus and Beyond Homework Help
Replies
1
Views
2K
Replies
3
Views
1K
  • Calculus and Beyond Homework Help
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
6
Views
2K
Back
Top