# How do you find the maximum, minimum and inflection points and concavity for the function #y=1/5(x^4-4x^3)#?

##### 1 Answer

Nov 5, 2016

Inflection point at x=0, Minima at x=3

concave up in

concave down in (0,3)

#### Explanation:

First get critical points by making

=

Now using second derivative test,

At x=0,

At x=3,

For concavity second derivative test can be used as shown below