Final answer:
To find the domain and range of a piecewise linear function, examine each piece for x and y value limitations, then combine results for the complete domain and range. X, Y, and Z are random variables with specific domains, and a negative value for Z is not possible. A discrete probability distribution must have non-negative probabilities that sum to one.
Step-by-step explanation:
To find the domain and range of a piecewise linear function, you will follow several steps:
- Examine each piece of the function and note the restrictions on the x-values (domain).
- For each piece of the function, determine the y-values produced (range).
- Combine the results from each piece, ensuring that overlaps in domain are addressed by including all x-values that give y-values in the function.
- Similarly, combine the y-values (range) from each piece to include all possible y-values the function can produce.
Consider the domains provided in the reference information:
- The domain of X, representing a student's major, is finite and categorical, listing all possible majors offered.
- The domain of Y, the number of classes taken in the previous semester, is a set of non-negative integers reflecting the possible number of classes.
- The domain of Z, the amount of money spent on books in the previous semester, starts from zero and can be any positive number.
X, Y, and Z are considered random variables because they can take on any value within their domains, and their specific values are not known until a survey or study is completed. Money spent on books (Z) having a value of -7 would not be a possible value, as the domain starts from zero and does not include negative numbers.
In terms of probability distribution for a discrete random variable, the two essential characteristics are:
- The probabilities are non-negative.
- The sum of the probabilities is one.