Level:
Project ID:
9000070407
Source Problem:
Accepted:
1
Clonable:
1
Easy:
0
Given the function \(f(x) = -x^{3} + 3x^{2} + 9x - 1\), find
the intervals where \(f\)
is a decreasing function.
\(\left (3;\infty \right )\)
\(\left (-\infty ;1\right )\)
\(\left (-1;3\right )\)
\(\left (1;\infty \right )\)