Basic Trigonometry – A Quick Recap

Last updated at August 13, 2026 by

Sin, cos, tan

Basic Trigonometry Quick Recap.jpg

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Value of sin, cos, tan at different angles

Basic Trigonometry – A Quick Recap - Part 2

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Basic Identities

cos 2 Β ΞΈ + sin 2 Β ΞΈ = 1

1 + tan 2 Β ΞΈ = sec 2 Β ΞΈ

1 + cot 2 Β ΞΈ = cosec 2 Β ΞΈ

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Transcript

In right triangle ABC sinβ‘πœƒ= (𝑠𝑖𝑑𝑒 π‘œπ‘π‘π‘œπ‘ π‘–π‘‘π‘’ π‘‘π‘œ π‘Žπ‘›π‘”π‘™π‘’ πœƒ)/π»π‘¦π‘π‘œπ‘‘π‘’π‘›π‘’π‘ π‘’ cosβ‘πœƒ= (𝑠𝑖𝑑𝑒 π‘Žπ‘‘π‘—π‘Žπ‘π‘’π‘›π‘‘ π‘‘π‘œ π‘Žπ‘›π‘”π‘™π‘’ πœƒ)/π»π‘¦π‘π‘œπ‘‘π‘’π‘›π‘’π‘ π‘’ tanβ‘πœƒ= (𝑠𝑖𝑑𝑒 π‘œπ‘π‘π‘œπ‘ π‘–π‘‘π‘’ π‘‘π‘œ π‘Žπ‘›π‘”π‘™π‘’ πœƒ)/(𝑠𝑖𝑑𝑒 π‘Žπ‘‘π‘—π‘Žπ‘π‘’π‘›π‘‘ π‘‘π‘œ π‘Žπ‘›π‘”π‘™π‘’ πœƒ) coπ‘ π‘’π‘β‘πœƒ= 1/sinβ‘πœƒ π‘ π‘’π‘β‘πœƒ= 1/cosβ‘πœƒ cotβ‘πœƒ= 1/tanβ‘πœƒ

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