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GR.7.4

Find angles in right-angled triangles

Recall and use trigonometric ratios to find angles in right-angled triangles

4 hand-picked video lessons for this topic, each checked for relevance and clarity, graded by difficulty and labelled by depth. Press play to watch — nothing loads from YouTube until you do.

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Grade 3–6 Core 🇬🇧 UK

Trigonometry | SOH CAH TOA | Sin, Cos, Tan

Cognito 509K views

Polished UK GCSE SOHCAHTOA lesson that clearly shows finding an unknown angle with inverse tan.

Jump to 0:28Labelling Sides 1:37Introduction to Trigonometric Ratios (Sin, Cos, Tan)2:05Using SOH CAH TOA 3:11Example 1: Finding an Unknown Angle 4:54Using Inverse Tan Function (Tan⁻¹)

Grade 4–6 Core 🇺🇸 US

Learn to find the missing angles for a triangle using inverse trig functions

Brian McLogan 2.4M views

Clear, focused walkthrough of using inverse trig to find missing angles in right triangles.

Grade 4–6 Core 🇬🇧 UK

Trigonometry Missing Angles - Corbettmaths

corbettmaths 103K views

Corbettmaths shows exactly how to find a missing angle from two given sides.

Grade 4–6 Core 🇬🇧 UK

Trigonometry: finding angles in right-angled triangles

revisemathsuk 484K views

Widely watched UK lesson on finding angle sizes with sine, cosine and tangent ratios.