x
f (x) = x2
 –2
4
−23
9
4
 –1
1
−21
1
4
  0
0
Values left to origin
as we move from left to right, the
height of the graph decreases
x
f (x) = x2
0
0
1
2
1
4
 1
1
3
2
9
4
 2
4
Values right to origin
as we move from left to right, the
height of the graph increases
Rationalised 2023-24
APPLICATION OF DERIVATIVES
153
(iv)
decreasing on I if x1 < x2 in I ⇒ f (x1) ≥ f (x2) for all x1, x2 ∈ I (v)
strictly decreasing on I if x1 < x2 in I ⇒ f (x1) > f (x2) for all x1, x2 ∈ I For graphical representation of such functions see Fig 6 2