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 = -5 to -4, it increases = [-5, -4]
For x = 1 to 3, it increases = [1, 3]
Answer: [-5, -4] , [1, 3]
