Problem 2.1: Decide whether the graph below is a function. [Solution]

Problem 2.2: Decide whether the graph below is a function. [Solution]

Problem 2.3: Decide whether the graph below is a function. [Solution]

Problem 2.4: What is the domain and range of the function f (x) =

? [Solution]

Problem 2.5: What is the domain and range of the function f (x) =

? [Solution]

Problem 2.6: Is the following a function: y = ±x? [Solution]

Problem 2.7: Is the following a function: y = | x|? [Solution]