Explanation:
Strictly increasing functions:
Let a function f(a) for x = a, then,
f(a + h), for x = a + h,
If f(a + h) > f(a), we say this a strictly increasing function, as with increase in x, f(x) also increases.
In the given graph, there are straight lines so you can say increasing interval would have +ve slope.
For x = -4 to 0, it increases = [-4, 0]
For x = 2 to 5, it increases = [2, 5]
Answer: [-4, 0], [2, 5]