direct proportion
What direct proportion means in Mathematics A-Level, as defined for AQA, WJEC.
Definitions of direct proportion
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Reference: AQA
A proportional relationship such as y = kx or y = kx², where given points can be used to find the constant of proportionality k.
Means y = kx for a constant of proportionality k ≠ 0, producing a straight line passing through the origin with gradient k.
Topics that use direct proportion
- B: Algebra and functions (AQA A-Level)
- Algebra and Functions (AS Unit 1: Pure Mathematics A) (WJEC A-Level)
Related terms
- Asymptotes
- Completing the square
- critical values
- Discriminant
- Factor theorem
- Graph transformations
- graphical intersections
- inverse proportion
Using direct proportion in the exam
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