The following table shows the temperature of water in a glass inside a room as a function of time:

[tex]\[
\begin{tabular}{|l|c|c|c|c|c|c|}
\hline
\begin{tabular}{l}
Time \\
$(\text{min})$
\end{tabular} & 0 & 10 & 20 & 30 & 40 & 50 \\
\hline
Temp (°F) & 32 & 40 & 60 & 68 & 68 & 68 \\
\hline
\end{tabular}
\][/tex]

Using correct notation, write the limit that states what the temperature of the water [tex]\( f(x) \)[/tex] goes towards as time [tex]\( x \)[/tex] goes towards 60 minutes. (Use the fact that the temperature of the water is going to continue to stay constant).



Answer :

To determine the temperature of the water as time approaches 60 minutes, we need to observe the trend in the given temperature data. Let's analyze the data available:

[tex]\[ \begin{array}{|c|c|c|c|c|c|c|} \hline \text{Time } ( \text{min} ) & 0 & 10 & 20 & 30 & 40 & 50 \\ \hline \text{Temp } (\text{°F}) & 32 & 40 & 60 & 68 & 68 & 68 \\ \hline \end{array} \][/tex]

We notice that as time increases, the temperature of the water initially rises and then stabilizes. Beyond 30 minutes, the temperature remains constant at 68°F.

To express this mathematically, we use the concept of limits. The notation for the limit of the temperature function [tex]\( f(x) \)[/tex] as [tex]\( x \)[/tex] (time) approaches 60 minutes is given by:

[tex]\[ \lim_{{x \to 60}} f(x) \][/tex]

From the data, we observe that the temperature [tex]\( f(x) \)[/tex] stabilizes at 68°F. Therefore, we can write:

[tex]\[ \lim_{{x \to 60}} f(x) = 68 \][/tex]

This means that as time approaches 60 minutes, the temperature of the water approaches 68°F and remains constant at that value.