Hello Guys, so far we have been learning about trigonometric identities in class. This post is about simplifying a trigonometric expression and proving a trigonometric equation using trigonometric identities.

Trigonometric  Identities: A trigonometric equation which is true for all permissible values of the variable for which both sides of the equation are defined is called Trigonometric Identity.

Example: There are:

                                

                        Reciprocal Identities

                              

               
                                   


There are sum and difference identities of sine, cosine, and tangent functions which can be used to simplify an expression or to prove a trigonometric equation.

Example 1:Simplify the expression using trigonometric identities.
                                
                  Rewrite tan as sin/cos.
                              
                              
                              
                              

Example 2: