The third pivot position in a matrix lies in column 3.

Module 2 Section 2.1: Properties of the Trigonometric Functions Recall the six trigonometric functions; y x y sin( )= , cos ( ) , tan( )= r r x csc( )= r , sec( )= r , cot( )= x y x y If we consider the unit circle then in each of these cases, r =1. Section 5.3 in the textbook does a very thorough job covering the topics: domain/range, period, signs, fundamental identities, finding exact values with identities. So we don't think writing anything here would add anything significant to the topics. Please read pages