Write an exponential function that models this situation. Let x represent the number of years since 2010 and let f(x)represent the number of lions.

Write an exponential function that models this situation Let x represent the number of years since 2010 and let fxrepresent the number of lions class=

Respuesta :

Answer:

[tex]f(x)=2(4)^x[/tex]

Explanations:

The standard exponential function is given as:

[tex]y=ab^x[/tex]

Given the coordinate points (2, 32) and (3, 128)

The two exponential functions will be;

[tex]\begin{gathered} y_1=ab^{x_1} \\ y_2=ab^{x_2} \\ \end{gathered}[/tex]

Substitute the given coordinates to have:

[tex]\begin{gathered} 32=ab^2 \\ 128=ab^3 \end{gathered}[/tex]

Divide both expressions to have:

[tex]\begin{gathered} \frac{128}{32}=\frac{ab^3}{ab^2} \\ b^{3-2}=4 \\ b=4 \end{gathered}[/tex]

Determine the value of "a"

[tex]\begin{gathered} 32=ab^2 \\ 32=a(4)^2 \\ 32=16a \\ a=2 \end{gathered}[/tex]

Substitute b = 4 and a = 2 into the original equation to have;

[tex]\begin{gathered} y=ab^x \\ y=2(4)^x \\ f(x)=2(4)^x \end{gathered}[/tex]

This gives the required exponential function