## Double-Angle Formulas

Select your language EnglishSpanish Let α be an angle. The double-angle (2α) trigonometric ratios can be expressed as a function of the trigonometric ratios of the angle α, that is, the double-angle formulas: Double-Angle...

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# Author: Bernat Requena Serra

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Double-Angle Formulas

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Sum and Difference Identities and Formulas

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Trigonometric ratios and Trigonometric Functions

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Arctangent

Select your language EnglishSpanish Let α be an angle. The double-angle (2α) trigonometric ratios can be expressed as a function of the trigonometric ratios of the angle α, that is, the double-angle formulas: Double-Angle...

Select your language EnglishSpanish Angle sum and difference identities express trigonometric functions of sums of angles α ± β in terms of functions of α and β. Using the sum and difference formulas allows us to...

Select your language EnglishSpanish Trigonometric ratios are defined as the ratios of the sides of a right triangle. There are six trigonometric ratios in total: sine, cosine, tangent, and their reciprocals, cosecant, secant and...

Select your language EnglishSpanish The arctangent (notation: arctan or tan-1) is the inverse function of the tangent. That is: As the arctangent and tangent are inverse functions, their composition is the identity. Thus: Properties...