College

A car was purchased in 2020 with an initial value of [tex]\$20,000[/tex]. The value of the car [tex]t[/tex] years after 2020 can be represented by the function [tex]f(t) = 20000(0.88)^t[/tex].

Which of the following functions best models the value of the car where [tex]n[/tex] represents the number of years after 2023?

Select one answer:

A. [tex]v(n) = 20000(0.88)^{3n}[/tex]

B. [tex]v(n) = 20000(0.88)^{n-3}[/tex]

C. [tex]v(n) = 20000(0.88)^3(0.88)^n[/tex]

D. [tex]v(n) = 20000^3(0.88)^3(0.88)^n[/tex]

Answer :

To solve this problem, we need to determine which function best models the value of the car, where [tex]\( n \)[/tex] represents the number of years after 2023.

The original function given is [tex]\( f(t) = 20000(0.88)^t \)[/tex], which models the car's value [tex]\( t \)[/tex] years after 2020. Since [tex]\( n \)[/tex] represents the years after 2023, we have the relationship that [tex]\( t = n + 3 \)[/tex] because 2023 is 3 years after 2020.

Let's substitute [tex]\( t = n + 3 \)[/tex] into the original function to model the value of the car [tex]\( n \)[/tex] years after 2023:

1. Start with the expression for [tex]\( t \)[/tex]: [tex]\( t = n + 3 \)[/tex].
2. Substitute into the original function:
[tex]\[
f(t) = 20000(0.88)^t = 20000(0.88)^{n+3}
\][/tex]
3. Use the property of exponents: [tex]\( (a^{b+c} = a^b \cdot a^c) \)[/tex], so:
[tex]\[
f(t) = 20000 \cdot (0.88)^3 \cdot (0.88)^n
\][/tex]

The expression [tex]\( 20000 \cdot (0.88)^3 \cdot (0.88)^n \)[/tex] can be simplified to:
[tex]\[
20000(0.88)^3(0.88)^n
\][/tex]

Among the answer choices, this matches option C:
[tex]\[
v(n) = 20000(0.88)^3(0.88)^n
\][/tex]

Therefore, the function [tex]\( v(n) = 20000(0.88)^3(0.88)^n \)[/tex] is the one that best models the value of the car where [tex]\( n \)[/tex] represents the number of years after 2023. So, the correct answer is option C.