Grade 10 Maths · Functions

State increasing and decreasing intervals

Give the x-values where a graph is going up or going down (for example y = x² is decreasing for x < 0 and increasing for x > 0).

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Hyperbola Increasing Decreasing | Grade 11 FunctionsKevinmathscience

Calculus Grade 12: Where is graph increasing / decreasingKevinmathscience

Increasing and Decreasing Functions - CalculusThe Organic Chemistry Tutor

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Question 9.1 · November 2024 · Paper 1 · National (DBE) · 2 marks

A (1; 9)

and

B (\frac{5}{2}; 8)

are the turning points of graph

f

below.

C (0; 7)

is the y-intercept of

f

9.1 For which values of

x

f

decreasing?(2)

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More past paper questions: state increasing and decreasing intervals

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3. Question 3.1.5(a) · March 2025 · Provincial · 2 marks
3.1 Given: $f (x) = \frac{2 x + 3}{- x - 3}$

Given: $f (x) = \frac{2 x + 3}{- x - 3}$
3.1.5 Determine the value(s) of $x$ for which:
3.1.5(a) $f$ is decreasing.(2)
Show the memo (2 ticks)Memo
1. ✓
  $x \in R$ $x \in R$
  1 mark · State increasing and decreasing intervals
2. ✓
  $x \neq = - 3$ $x \neq = - 3$
  1 mark · State increasing and decreasing intervals
4. Question 3.2.2 · March 2022 · Provincial · 2 marks
3.2 The graph of $g (x) = - 2 cos 2 x$ for $x \in [- 18 0^{\circ}; 18 0^{\circ}]$ is drawn below.
3.2.2 For which values of $x$ is $g (x)$ strictly decreasing in the interval $x \in [- 18 0^{\circ}; 0^{\circ}]$ ?(2)
Show the memo (1 tick)Memo
1. ✓
  Identify decreasing interval from graph $- 9 0^{\circ} < x < 0^{\circ}$
  2 marks · State increasing and decreasing intervals
5. Question 7.2 · November 2023 · Paper 1 · Provincial · 1 mark
The diagram below shows the graphs of $f (x) = a x^{2} + b x + c$ and $g (x) = m x + q$ . D $(- 1; 4)$ and F $(1; 6)$ are points of intersection of $f$ and $g$ . T and U are the $x$ -intercepts of $f$ , E $(0; 6)$ the $y$ -intercept of $f$ and S is the $x$ -intercept of $g$ . VW is a straight line drawn parallel to the $y$ -axis. $Diagram for this question$
7.2 For which values of $x$ is $f$ decreasing?(1)
Show the memo (1 tick)Memo
1. ✓
  Answer $x > \frac{1}{2}$
  1 mark · State increasing and decreasing intervals

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