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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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 In any non-equilateral triangle the orthocenter (H), the centroid (G) and the circumcenter (O) are aligned. The line that contains these three points is called the Euler line. In an...
Select your language EnglishSpanish The hypotenuse of a right triangle (or right-angled triangle) is the side opposite its right angle. It is the longest side of a right triangle. We can find the hypotenuse...
Select your language EnglishSpanish The area of any triangle can be calculated by knowing one side and the height (or altitude), associated with that side. This side serves as the base. In fact the...
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...
Select your language EnglishSpanish Some classical triangle centers are: Centroid (G) Orthocenter (H) Circumcenter (O) Incenter (I) Centroid of a Triangle The centroid of a triangle (or barycenter of a triangle) G is the...