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 Triangles can be classified by their sides or by their angles. According to these, we can assert that there are basically six different types of triangles: equilateral triangle, isosceles triangle,...
Select your language EnglishSpanish The area of an isosceles triangle is calculated from the base b (the non-repeated side) and the height (h) of triangle corresponding to the base. The area is the product...
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 Euclidean geometry, two objects are similar if they are the same shape, regardless of their size. Two triangles are similar if, and only if, their angles are congruent (equal)...
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 perimeter of an isosceles triangle is obtained as the addition of the three sides of the triangle. Having two equal sides, the perimeter is twice the repeated side (a)...