This fast math trick can be used to mentally work out the main basic trigonometric ratios instantly! With this fast mental math technique you can work out the sin, the cos, and even the tan of the most common angles in no time at all!
Trigonometry is a branch of mathematics that deals with triangles, particularly those plane triangles in which one angle has 90 degrees (right triangles). Trigonometry deals with relationships between the sides and the angles of triangles and with the trigonometric functions, which describe those relationships.