Handy Trigonometry: Right Triangles, Degrees and Radians, Identities, and Formulas

By Mark Ryan

Part of Calculus For Dummies Cheat Sheet

This trigonometry info will help you deal with triangles, finding their relationships between the sides and angles of right triangles, and make calculations based on these relationships.

Right triangle trig

SohCahToa:

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Degrees and radians

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Identities

Reciprocal identities

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Quotient identities:

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Pythagorean identities:

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Formulas

Half-angle formulas:

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Double-angle formulas:

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Reduction formulas:

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