Trigonometric Identities

List of identities

Given two functions f and g, we say f = g if f(x) = g(x) for all every x in the domain of both f and g.

Quotient identities:

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \tan(\theta) = \frac{\sin(\theta)}{\cos(\theta)} ~ \cot(\theta) = \frac{\cos(\theta)}{\sin(\theta)}}

Reciprocal Identities:

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \csc(\theta) = \frac{1}{\sin(\theta)}~\sec(\theta) = \frac{1}{\cos(\theta)}~\cot(\theta) = \frac{1}{\tan(\theta)}}

Pythagorean Identities:

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \sin^2(\theta) + \cos^2(\theta) = 1~ \tan^2(\theta) + 1 = \sec^2(\theta)~ \cot^2(\theta) + 1 = \csc^2(\theta)}

Even-Odd:

Sine, Cosecant, Tangent, and Cotangent are all odd functions, so f(-x) = -f(x). The other two trigonometric functions cos and secant are even, so f(-x) = f(x)

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