ALGEBRA I Unit 1 Section 3 Function Notation

– ALGEBRA I – Unit 1 – Section 3 Function Notation Suppose that you have a two-variable relationship… To generate ordered pairs, you need to choose values for “x” and evaluate…

– ALGEBRA I – Unit 1 – Section 3 Function Notation Here is a table to illustrate some answers: X 4 9 0 Work Y Ordered Pair 2(4) + 6 = 8 + 6 = 14 14 (4, 14) 2(9) + 6 = 18 + 6 = 24 24 (9, 24) 2(0) + 6 = 0 + 6 = 6 6 (0, 6) 3 2(3) + 6 = 6 + 6 = 12 12 (3, 12)

– ALGEBRA I – Unit 1 – Section 3 Function Notation To change this to function notation, it is just a matter of switching the variable… Let’s talk about functions notation in a little more detail…

Function Notation FUNCTION NOTATION –an alternative way to write an equation that allows you to “name” different equations Independent values that are input Variable into a function Function Name This is read as “f of x”.

Function Notation What is the purpose of writing a relationship in function notation? 1. Function notation allows you distinguish that a relationship is a function and has the caveat that each member of the domain matches with exactly on value in the range. Function (or an equation) Just an equation (not a function)

Function Notation What is the purpose of writing a relationship in function notation? 2. Function notation allows you to give a relationship a “name” and distinguish between different relationships. This shows that there are three distinct relationships. Are all of the “y’s” referring to same thing?

Function Notation Suppose that you are given a problem like the following… This means that you need to plug 3 in for “x” and simplify. It is just like evaluating an expression. The ordered pair would be:

Function Notation Suppose that you are given a problem like the following… This means that you need to plug 9 in for “x” and simplify. It is just like evaluating an expression. The ordered pair would be:

Function Notation Notice that the process is exactly same as if you were still using “y’s” rather than “f(x)’s”… You can compare the charts… X 4 9 0 Work Y Ordered Pair 2(4) + 6 = 8 + 6 = 14 14 (4, 14) 2(9) + 6 = 18 + 6 = 24 24 (9, 24) 2(0) + 6 = 0 + 6 = 6 6 (0, 6) 3 2(3) + 6 = 6 + 6 = 12 12 (3, 12)

Function Notation Notice that the process is exactly same as if you were still using “y’s” rather than “f(x)’s”… You can compare the charts… X Work F(x) Ordered Pair 4 2(4) + 6 = 8 + 6 = 14 14 (4, 14) 9 2(9) + 6 = 18 + 6 = 24 24 (9, 24) 0 2(0) + 6 = 0 + 6 = 6 6 (0, 6) 3 2(3) + 6 = 6 + 6 = 12 12 (3, 12)

Try These Problems… Evaluate the following functions. 1. f(x) = 5 x 2 Find f(3). 2. g(y) = 5 y 2 + 4 Find g(0). 3. h(t) = 2 t – 9 Find h(20). 4. T(x) = 3 x 3 – 4 x Find T(2). **The answers can be found at the end of the Power. Point.

ALGEBRA IS FUN AND EASY! **Answers: 1) 45 2) 0 3) 31 4) 16