# 9.1.23 PreCalculus

1. Read the next journal entry and write a response.

2. Read 3.1 and write the definition of a function along with the 9 basic functions given on pages 174 and 175. You may want to include in your definition the information on Pages 187 and 188 (in 3.2) about these functions. The book did not include the linear function, y=mx+b, in their list, but we will include it in ours.

3. There are three ways to determine if a relation is a function: picture - does the picture pass the vertical line test; list of points (x,y) - if the x's repeat the list of points do not represent a function; equation - if the equation has a + and - in front of a radical, it is not a function, if the equation has an even power on the y variable, it is not a function. All other functions should be OK.