2022-169

A critical point for a function $f$ is a value $c$ in the domain of $f$ where $f^{\prime }(c)=0$ or $f^{\prime }(c)$ does not exist.  Choose the statement that presents the critical points of $$f(x)=x^{3/5}(4-x)$$

1. 0 and 2/3
2. 2/3 and 4/3
3. 4/3 and 3/2
4. 0 and 3/2
5. None of the above.

Original idea by: Rubens de Castro Pereira