An inflection point is any point on a graph of a function where the concavity of the function changes (ie. from concave up to concave down). For a function to have an inflection point it must have a second derivative. Inflection points can be found on a graph by checking for locations where the second derivative switches signs.
Given the function
is shown in blue and the second derivative of is also shown in green.
Checking right before the potential inflection point
Checking right after the potential inflection point
| Concave Down | Inflection Point | Concave Up |
Given the function
is shown in blue and the second derivative of is also shown in green.
Checking right before the potential inflection point
Checking right after the potential inflection point
Because the second derivative stays positive before and after the potential inflection point
There are no inflection points on the graph of the function