Determine the intervals on which f(x) is positive and on which f(x) is negative

Question

f(x)=x⁵+x⁴-3x³-3x²-9x-9

f(x)>0 if......

f(x)<0 if ......

Answer 1

f(x) is positive from about -2.4 < x < 0 and x> 2.1

and

f(x) is negative from about 0 < x < 2.1 and when x < -2.4

graph it with Desmos graphing calculator

and you can read it off the graph