Determine whether each statement is true or false. Explain your reasoning.
The equation z = y4 describes y as a function of z.
False. For any value of z there are two possible values of y. For example, if z = 16 then y can be ± 2. Watch out for these sneaky functions where the independent variable is raised to by even-valued exponent. They have two roots, the positive number and their evil negative twin.