# Lesson 3

Using Function Notation

• Let’s use function notation to talk about points.

### 3.1: Which One Doesn’t Belong: Function Notation

Which one doesn’t belong?

• $$f(0) = 2$$
• $$(0,5)$$
• $$y = x+2$$

### 3.2: Points into Function Notation and Back

1. A function is given by the equation $$y = f(x)$$. Write each of these coordinate pairs in function notation.
1. $$(2,3)$$
2. $$(\text{-}1,4)$$
3. $$(0,3)$$
4. $$(4,0)$$
5. $$\left( \frac{2}{3}, \frac{3}{4} \right)$$
2. A function is given by the equation $$h(x) = 5x - 3$$. Write the coordinate pair for the point associated with the given values in function notation.
1. $$h(3)$$
2. $$h(\text{-}4)$$
3. $$h\left( \frac{2}{5} \right)$$

### 3.3: A Graph with Properties

1. Draw a graph of function $$y = g(x)$$ that has these properties:

• $$g(0) = 2$$
• $$g(1) = 3$$
• $$(2,3)$$ is on the graph
• $$g(5) = \text{-}1$$
2. Han draws this graph for $$g(x)$$. What is the error?