The complementary angles are those that added are equal to the value of a right angle, that is, a 90 degree angle. If the sides are common are one to the side of the other (straight) the angle right will be appreciated, however not necessarily complementary angles have to be consecutive, sufficient that the sum of both is of 90º. For example, the two non-right angles of a right triangle are complementary and are not consecutive.
To calculate the size of a complementary angle is taken as a reference right angle and subtracts the first angle which is find the plug. Then there is an example like this: The right angle is equal to 90 ° minus the angle we have which is 60 °, the complementary angle is 30 °.
Whether or not they are consecutive, complementary angles will always add up to 90 degrees mathematically. Having understood the example well, the 30 degree angle is the complement of the first one, these angles form a right triangle since the angles in a right triangle are one of 90º and the other two must add 90 with that of the adjacent leg and multiply by the hypotenuse. Therefore, the sine of α is equal to the cosine of β and the sine of β equal to the cosine of α since they belong to the same right triangle.
The diagonal of a rectangle also sets complementary angles (90 °) with the adjacent sides. Light forms non-consecutive complementary angles through a lens.
