Answer:
30.a) Domain: [-6, 6]
30.b) Range: [-3, 7]
30.c) Function: No
31.a) Domain: [-2, 2]
31.b) Range: [-6, 6]
31.c) Function: No
Explanation:
Definitions
- An open circle indicates the value is not included in the interval.
- A closed circle indicates the value is included in the interval.
- An arrow shows that the function continues indefinitely in that direction.
Interval notation
- ( or ) : Use parentheses to indicate that the endpoint is excluded.
- [ or ] : Use square brackets to indicate that the endpoint is included.
The domain is the set of all possible input values (x-values).
The range is the set of all possible output values (y-values).
Question 30
The graph is a conic section (ellipse) and therefore it is not a function.
The smallest x-value is x = -6 and the greatest x-value is x = 6.
The smallest y-value is y = -3 and the greatest y-value is y = 7.
Therefore, the domain and range in interval notation are:
- Domain: [-6, 6]
- Range: [-3, 7]
The graph is a not a function as almost all the inputs (x-values) are related to more than one output (y-value).
Question 31
From inspection of the graph, the endpoints of the continuous line are:
Both endpoints are closed circles, so the values are included in the domain and range.
The smallest x-value is x = -2 and the greatest x-value is x = 2.
Therefore, the domain in interval notation is:
The smallest y-value is y = -6 and the greatest y-value is y = 6.
Therefore, the range in interval notation is:
The graph is a not a function as not all inputs (x-values) are related to one output (y-value).