👉 Learn all about the trigonometry of right triangles. A right triangle is a triangle that has 90 degrees as one of its angles. The trigonometric identities of right triangles give us the ...

👉 Learn how to evaluate inverse trigonometric functions. When an angle is unknown but the value of one of the trigonometric functions of the angle is known, we can evaluate the value of the angle ...

Angles inside regular polygons can usually be calculated by splitting the polygon into triangles around the centre. Split the regular pentagon into triangles. Each angle at the centre is \(72^\circ\) ...