IP EMaths Notes (Upper Sec, Year 3-4): 09) Right-Triangle Trigonometry

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08 Nov 2025, 00:00 Z

Q: What does IP EMaths Notes (Upper Sec, Year 3-4): 09) Right-Triangle Trigonometry cover?
A: Use sine, cosine, and tangent ratios alongside Pythagoras to evaluate sides and angles quickly.

Right-angled triangles provide fast access to heights, bearings, and resultant forces. Remember which side is opposite, adjacent, or hypotenuse relative to the marked angle.

Keep the full topic roadmap handy via our IP Maths tuition hub so you can jump into related drills, quizzes, or diagnostics as you move through these notes.

Ratio recap

$\sin \theta = \dfrac{\text{opposite}}{\text{hypotenuse}}$ .
$\cos \theta = \dfrac{\text{adjacent}}{\text{hypotenuse}}$

IP EMaths Notes (Upper Sec, Year 3-4): 09) Right-Triangle Trigonometry

Ratio recap

Worked example - Ladder against a wall

Worked example - Find an acute angle from side lengths

Worked example - Two-step height and distance problem

Practice Quiz

Try this

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