Find the critical value(s) by setting the first derivative equal to zero and solving for the x value(s).
1=0 is not a true statement. A critical value cannot be found using the first derivative.
If f'(x)>0 the function increases on the interval.
If f'(x)<0 the function decreases on the interval.
The domain for the function is all real values for x.
Notice that f'(0)=undefined. This means the slope of the function at x=0 does not exist.
Choose an x value less than 0.
f'(-1)=1/3 Since f'(-1)>0 the graph is increasing on the interval (-`oo,0).`
Choose an x value greater than 0.
f'(1)=1/3 Since f'(1)>0 the graph is increasing on the interval (0, `oo).`
Since the function does not change direction there will not be a relative extrema.