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 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 Finding the area of a triangle is depending on the type of triangle or which sides and angles we know. The most common formula for finding the area of a...
Select your language EnglishSpanish The angle bisector of a triangle is a line segment that bisects one of the vertex angles of a triangle, and ends up on the corresponding opposite side. There are...
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 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 Every triangle has lines (also called cevians) and points that determine a number of important elements. There are many different constructions that find a special point associated with a triangle,...
Select your language EnglishSpanish There are several theorems that are attributed to Thales of Miletus, we are going to focus especially on two of them: Thales’ Theorem Thales’ Theorem is a special case 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....