Question

What are all the points of inflection of `f(x)=(1/12)x^4-2x^2+15`?

Answer 1

`(+-2, 21/3)`. See the Socratic graph, for these locations.

Explanation:

`f''=x^2-4=0, at x =+-2`, and here

`f'''=2x=+-4 ne=0`. So,

the POI are `(+-2, 21/3)`.

graph{(1/12x^4-2x^2+15-y)((x+2)^2+(y-23/3)^2-.1)((x-2)^2+(y-23/3)^2-.1)=0x^2 [-40, 40, -20, 20]}