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 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 A right triangle is a polygon with three sides that has one angle (α) that measures 90° which is the largest angle of the right triangle. If we add all...
Select your language EnglishSpanish The incenter of a triangle (I) is the point where the three interior angle bisectors (Ba, Bb y Bc) intersect. The angle bisector of a triangle is a line segment...
Select your language EnglishSpanish Heron’s Formula gives the area of a triangle when we know all three sides. The area is calculated from the semiperimeter of the triangle, s and the length of the...
Select your language EnglishSpanish Geometric mean (or mean proportional) appears in two popular theorems regarding right triangles. The geometric mean theorem (or altitude theorem) states that the altitude to the hypotenuse of a right...
Select your language EnglishSpanish The median of a triangle is a line segment that joins one of its vertices with the center of the opposite side. Every triangle has three medians (ma, mb and...
Select your language EnglishSpanish The basic elements of a triangle are: Vertices: points where two sides meet. It has 3 vertices (A, B, and C). Sides: line segments that join two consecutive vertices of...
Select your language EnglishSpanish In a right triangle, different elements can be distinguished, referring to its sides and angles. Legs (or cathetus): are the sides of the triangle that together form the right angle....