Intro to Functions

Intro to Functions - Relation A relation is a set of...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Relation A relation is a set of ordered pairs where the first components of the ordered pairs are the input values and the second components are the output values. Function A function is a relation that assigns to each input number EXACTLY ONE output number. Be careful. Not every relation is a function. A function has to fit the above definition to a tee. Domain The domain is the set of all input values to which the rule applies. These are called your independent variables . These are the values that correspond to the first components of the ordered pairs it is associated with. Range The range is the set of all output values. These are called your dependent variables . These are the values that correspond to the second components of the ordered pairs it is associated with.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Example 1 : Determine if the given relation is function or not. Give its domain and range. {(1, 2), (1, -2), (2, 3), (3, 4)} Is this a function or not? We need to ask ourselves, does every first element (or input) correspond with EXACTLY ONE second element (or output)? In this case, the answer is no. The input value of 1 goes with two output values, 2 and -2. It only takes one input value to associate with more than one output value to be invalid as a function. So, this relation would not be an example of a function. Domain We need to find the set of all input values. In terms of ordered pairs, that correlates with the first component of each one. So, what do you get for the domain? If you got {1, 2, 3}, you are correct! Note that if any value repeats, we only need to list it one time. Range We need to find the set of all output values. In terms of ordered pairs, that correlates with the second component of each one. So, what do you get for the range? If you got {2, -2, 3, 4}, you are absolutely right! Example 2 : Determine if the given relation is function or not. Give its domain and range. {(5, 10), (10, 10), (15, 10)}
Background image of page 2
Is this a function or not? We need to ask ourselves, does every first element (or input) correspond with EXACTLY ONE second element (or output)? In this case, the answer is yes. 5 only goes with 10, 10 only goes with 10, and 15 only goes with 10. Note that a relation can still be a function if an output value associates with more than one input
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 14

Intro to Functions - Relation A relation is a set of...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online