This table represents a quadratic function with a vertex at [tex]$(1,1)$[/tex]. What is the average rate of change for the interval from [tex]$x=5$[/tex] to [tex]$x=6$[/tex]?

\begin{tabular}{|c|c|}
\hline
[tex]$x$[/tex] & [tex]$y$[/tex] \\
\hline
1 & 1 \\
\hline
2 & 2 \\
\hline
3 & 5 \\
\hline
4 & 10 \\
\hline
5 & 17 \\
\hline
6 & ? \\
\hline
\end{tabular}



Answer :

To determine the average rate of change for the interval from [tex]\( x = 5 \)[/tex] to [tex]\( x = 6 \)[/tex] on this quadratic function, we follow these steps:

1. Identify coordinates for the given interval:
- The coordinates for [tex]\( x = 5 \)[/tex] are given as [tex]\( (5, 17) \)[/tex].
- The value for [tex]\( y \)[/tex] when [tex]\( x = 6 \)[/tex] is not provided in the table. However, based on the question setup, we need to determine this point, presumed to be [tex]\( (6, 26) \)[/tex].

2. Formula for Average Rate of Change:
- The average rate of change of a function over an interval [tex]\([a, b]\)[/tex] is given by:
[tex]\[ \frac{f(b) - f(a)}{b - a} \][/tex]
- In this context, [tex]\( a = 5 \)[/tex], [tex]\( b = 6 \)[/tex], [tex]\( f(a) = 17 \)[/tex], and [tex]\( f(b) = 26 \)[/tex].

3. Plug in the values:
[tex]\[ \frac{f(6) - f(5)}{6 - 5} = \frac{26 - 17}{6 - 5} \][/tex]

4. Calculate the differences and ratio:
[tex]\[ \frac{26 - 17}{1} = \frac{9}{1} = 9 \][/tex]

So, the average rate of change for the interval from [tex]\( x = 5 \)[/tex] to [tex]\( x = 6 \)[/tex] is [tex]\( 9.0 \)[/tex].