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Brunll
Aug26-08, 03:13 PM
1. The problem statement, all variables and given/known data
Temperature readings T (in degrees celcius) were recorded every hour starting at midnight on a day in april in Whitefish, Montana.The time x is measured in hours from midnight.The data are giving in the table at the left

x(h) T(°C)

0 6.5
1 6.1
2 5.6
3 4.9
4 4.2
5 4.0
6 4.0
7 4.8
8 6.1
9 8.3
10 10.0
11 12.1
12 14.3






2. Relevant equations

Estimate the instantaneous rate of change at noon.

3. The attempt at a solution
I tried to understand the solution but still dont get it.so could somebody help me?








3. The attempt at a solution

snipez90
Aug26-08, 03:21 PM
With just that set of data, noon is an endpoint if you plot it. I mean you could find the average temperature change between 11 AM and noon but that would not be a great estimate. I'm not sure what kind of solution you're looking for here. The best way to estimate the instantaneous rate of change is to plot the graph, use a ruler to draw a tangent line, and try figuring out the slope, but with the data set you've given, this won't work out too well.

Brunll
Aug26-08, 04:03 PM
The best way to estimate the instantaneous rate of change is to plot the graph, use a ruler to draw a tangent line, and try figuring out the slope, but with the data set you've given, this won't work out too well.

Thanks!I'll try it.

symbolipoint
Aug26-08, 06:55 PM
Brunll, you could use the set of points and graph to develop a function, F(x) = something, and perform differentiation on it, and find the value of the derivative at the point where x=12

kenewbie
Aug27-08, 02:22 AM
Brunll, you could use the set of points and graph to develop a function, F(x) = something, and perform differentiation on it, and find the value of the derivative at the point where x=12

That data do not easily map to a function.

I would go with the slope of the tangent.

k

Redbelly98
Aug27-08, 08:43 PM
... you could find the average temperature change between 11 AM and noon but that would not be a great estimate.



... The best way to estimate the instantaneous rate of change is to plot the graph, use a ruler to draw a tangent line, and try figuring out the slope, but with the data set you've given, this won't work out too well.

I think the 1st method mentioned here is more accurate than the 2nd method.

granpa
Aug27-08, 09:06 PM
first convert the data to change in temperature per hour.

next to that make a chart of change in change in temperature per hour.