Find the interval in which is increasing or decreasing ?
we have
Critical points
⇒x = 0, –1
Clearly,f'(x) > 0 if x>0
And f'(x) < 0 if –1 < x < 0 or x < –1
Hence, f(x) increases in (0,), decreases in (–, –1) U (–1, 0)