The table of ordered pairs [tex]\((x, y)\)[/tex] represents an exponential function. Write an equation for the function.

[tex]\[
\begin{tabular}{|c|c|}
\hline
$x$ & $y$ \\
\hline
-1 & 3 \\
\hline
0 & 6 \\
\hline
1 & 12 \\
\hline
2 & 24 \\
\hline
\end{tabular}
\][/tex]



Answer :

Certainly! To write an equation for the given exponential function, we need to follow some steps systematically.

The general form of an exponential function is:
[tex]\[ y = a \cdot b^x \][/tex]

Here, [tex]\(a\)[/tex] represents the initial value of [tex]\(y\)[/tex] when [tex]\(x = 0\)[/tex], and [tex]\(b\)[/tex] is the base of the exponential function which represents the constant ratio between successive [tex]\(y\)[/tex]-values.

Let's break down the process step by step:

1. Identify the initial value [tex]\( a \)[/tex]:
The initial value [tex]\( a \)[/tex] can be directly taken from the table where [tex]\(x = 0\)[/tex].
From the table:
[tex]\[ \begin{array}{|c|c|} \hline x & y \\ \hline 0 & 6 \\ \hline \end{array} \][/tex]
So, [tex]\( a = 6 \)[/tex].

2. Determine the base [tex]\( b \)[/tex]:
To find the base [tex]\( b \)[/tex], we'll use the ratio of [tex]\( y \)[/tex]-values for successive values of [tex]\( x \)[/tex].
For [tex]\(x = 1\)[/tex] and [tex]\(x = 2\)[/tex]:
[tex]\[ \frac{y(2)}{y(1)} = \frac{24}{12} = 2 \][/tex]
The base [tex]\( b \)[/tex] is 2.

3. Form the equation:
Now that we know [tex]\( a = 6 \)[/tex] and [tex]\( b = 2 \)[/tex], we can write the equation of the exponential function as:
[tex]\[ y = 6 \cdot 2^x \][/tex]

Let's confirm the equation with all given points from the table:
- For [tex]\( x = -1 \)[/tex]:
[tex]\[ y = 6 \cdot 2^{-1} = 6 \cdot \frac{1}{2} = 3 \][/tex]
- For [tex]\( x = 0 \)[/tex]:
[tex]\[ y = 6 \cdot 2^0 = 6 \cdot 1 = 6 \][/tex]
- For [tex]\( x = 1 \)[/tex]:
[tex]\[ y = 6 \cdot 2^1 = 6 \cdot 2 = 12 \][/tex]
- For [tex]\( x = 2 \)[/tex]:
[tex]\[ y = 6 \cdot 2^2 = 6 \cdot 4 = 24 \][/tex]

Each calculated [tex]\( y \)[/tex]-value matches the corresponding [tex]\( y \)[/tex]-value in the table, verifying our equation.

Thus, the equation for the given exponential function is:
[tex]\[ y = 6 \cdot 2^x \][/tex]