LEARN TRIGONOMETRY

An Identity is an equality that is true for any value of the variable. (An equation is an equality that is true only for certain values of the variable.) We use an identity to give an expression a more convenient form. The trigonometric identities are important identities that involve sums or differences of trigonometric angles. An identity that shows that the cosine of the difference of two angles is related to the cosines and sines of the angles themselves. Trigonometric identities involving sin 2x of cos 2x are called double-angle identities. These identities are derived using the sum and difference identities.

Inverse Trigonometric Functions:

Trigonometric inverse function returns an angle corresponding to a real number, following certain rule. They are inverse functions corresponding to trigonometric functions. Inverse trigonometric functions are also called arc functions. This is an alternative notation. The corresponding functions are arcsine, arccosine, arctangent etc In order to define, an inverse function; we require having one-one relation in both directions between domain and range. The function needs to be a bijection.

Trigonometric Functions:

Below is the list of the Trigonometric functions.

Sine Function: sine (θ) = Opposite /Hypotenuse
Cosine Function: cos (θ) = Adjacent/Hypotenuse
Tangent Function: tan (θ) = Opposite /Adjacent