Maths · GCSE · Geometry & Measures

Exact trigonometric values

gcse-math-g21Free1:57Heddy Score 2 of 7, below the standard

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What you need to know

  • Exact values come from the 30-60-90 and 45-45-90 triangles.
  • sin 30° and cos 60° both equal one half.
  • tan 45° equals 1.

In this clip

11:49–14:44Recurring decimals to fractionsmh7
14:44–15:57Prime factorisationm26
15:57–19:04Fractional indicesmh6
19:04–22:40Surds: exact rootsmh4
22:40–24:12Standard form: large numbersm46
24:12–26:10Calculating in standard formm48
26:50–27:45Expanding a single bracketm61
27:45–35:11Algebraic fractionsgcse-math-a4g
35:11–39:28Building equations from problemsm84
39:28–41:35Solving linear inequalitiesm73
41:35–43:58Solving quadratics by factorisingmh8
43:58–46:17Tangent to a circlegcse-math-a16b
46:17–52:23Reading a quadratic graphgcse-math-a11a
52:23–56:09Perpendicular linesgcse-math-a9d
56:09–59:46Gradient of a curvegcse-math-a15a
59:46–62:15Angles in polygonsm16
64:12–66:08Arcs & sectorsmh14
66:08–70:18Surface area of prismsm132
70:18–72:35Volume of cuboidsm117
72:35–74:20Pythagoras: the hypotenusem136
74:20–76:17Exact trigonometric valuesgcse-math-g21
76:17–85:17Vector proofsgcse-math-g25b
86:10–97:15Ratio & proportion problemsm15
97:15–100:04Ratio ↔ fraction linksm88
100:04–104:02Proportion formulaemh13
104:02–106:22Density and pressuregcse-math-r11b
108:39–120:20Independent eventsm160
120:20–122:08Cumulative frequency graphsgcse-math-s3b
122:08–123:30Quartiles & interquartile rangemh20
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Heddy Score2/7, Below the standard
  • 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 · not judged yet. 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.
★ passed · ☆ pending · ✕ failed
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How the Heddy Score works

Why we picked it

Topic-by-topic revision built around the May 2023 Higher Paper 1; the topics are standard GCSE content and suit Year 11 Higher students.

The GCSE Maths Tutor on YouTubechecked 2026-10-16