# The function c=45n+5 can be used to determine the cost, c, for a person to purchase n tickets to a concert. Each person can purchase at most 6 tickets. What is an appropriate domain for the function?

Dec 1, 2016

$0 \le n \le 6$

#### Explanation:

Basically the 'domain' is the set of input values. In other wards it is all the permitted independent variable values.

Suppose you had the equation:$\text{ } y = 2 x$
Then for this equation the domain is all the values that may be assigned to the independent variable $x$

Domain: The values you may chose to assign.
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For the given equation: $c = 45 n + 5$

$n$ is the independent variable which logically would be the count of tickets.

We are told that no more than 6 tickets may be purchased by any one person. So $n$ can only take on the whole number values between and including 0 to 6

So the domain is written as: $\text{ } 0 \le n \le 6$
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~~~~~~~~~~~~~~~ Memory aid ~~~~~~~~~~~~~~~~~~~~~~~~~~~
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In the alphabet d for domain comes before r for range

You have to 'plug' in a value before you get your answer

So d first $\to$ input first
and r next $\to$ answer second

$d \to \text{ input }$
$r \to \text{ output}$