Maths · GCSE · Algebra
Function notation f(x)
Function notation f(x)Free8:33Heddy Score 3 of 7, below the standard
What you need to know
- A function takes each input and gives exactly one output, like a function machine.
- A rule such as y = 2x can be shown as a table of inputs and outputs and then plotted as a graph.
- f(x) is read 'f of x'; f is the name of the function, not a number multiplied by x.
- To find f(4) when f(x) = 3x + 2, replace every x with 4 to get 14.
In this clip
Runs 8:33, from 2:23 to 10:56 of the full video.
Heddy ScoreSeven checks every clip must pass before students see it: trusted, on the map, accurate, focused, accessible, safe, and proven by students.3/7, Below the standard
See the seven stars
- Trusted source · passed. The creator's own upload, live and playable here.
- On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
- Spec-true · not judged yet. Accurate, and right for the current UK specification.
- Focused · passed. One idea, short enough to watch in one go.
- Accessible · passed. Good captions, clear sound and pictures.
- Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
- Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
Our students
Not enough students yet
Our own students' answers. These are what move ★7 Proven.On YouTube
How the Heddy Score works4.16M views · 63.2K likes · mathantics 3.88M subscribers
As reported by YouTube on 2026-11-02. Not part of the Heddy Score.Why we picked it
A clear, visual explanation of what a function is, ending with exactly how to read and evaluate f(x) notation.
mathantics on YouTubechecked 2026-10-22
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