tangent: Quick Facts

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Facts

Also Known As	tan

Photos

Diagram of a right triangle labeled with sides a, b, and hypotenuse c, alongside formulas for the six trigonometric functions-sine, cosine, tangent, cosecant, secant, and cotangent-each defined by ratios of the triangle's sides.

Four graphs display the curves of sine, cosine, tangent, and cotangent functions, each labeled with x- and y-axes, key angles in radians, and typical wave or asymptote patterns.

A geometric diagram illustrating Fermat's tangent method, showing a curve intersecting a triangle with labeled points, axes, and segments representing variables x, epsilon, y, and y1.

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Topics

law of tangents trigonometric function cosine sine cosecant cotangent secant