Reciprocal function

Definition

A function of the form $y=\frac{k}{x}$ , where $k$ is a constant and ; is the simplest example.

Specification A12 · Paper 1, Paper 2, Paper 3

A function involving division by the variable; the required basic reciprocal function is $y=\frac{1}{x}$ , where .

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k

x\ne0

y=\frac1x

Used by AQA, Edexcel and OCR

x \neq = 0

Cubic and reciprocal functions are both non-linear, but their graphs behave very differently. A cubic is one continuous curve.

Specification A12 · Paper 1, Paper 2, Paper 3

A function in which the output is the reciprocal of the non-zero input; for example, $y=1/x$ .
Revise: Reciprocal and Exponential Graphs

Specification 7.01b · Paper 1 (Foundation), Paper 2 (Foundation), Paper 3 (Foundation), Paper 4 (Higher), Paper 5 (Higher), Paper 6 (Higher)