1. Sine Equation on TI

2. For this activity please refer to Portland Monthly Climate Summary
Use the Average Max Temps.
Average
Max. Temperature (F)
Jan
45.1
Feb
50.6
Mar
55.3
Apr
60.8
May
67.5
Jun
73.2
Jul 80
Aug
79.9
Sep 75
Oct
63.6
Nov
52.5
Dec 46

3. I. Entering Data

4. Press the STAT Key
Press ENTER

5. Enter x values in L1 Enter y values in L2
If columns are not clear let me know.
Enter x values in L1
Enter y values in L2

6. Data is now entered and saved on your calc.
Press QUIT

7. II. PLOTING DATA

8. Press the STAT Key
Press
2nd y=
STAT PLOT

9. Make sure all the plots are off.
Press ENTER

10. Use the arrow keys and enter key. Make sure the screen matches

11. ZOOM
Choose 9: Zoomstat

12. III. Calculating the sine equation and graphing the equation.

13. Disclaimer: to apply the SinReg you must have several pairs of data, where the x values are equally spaced.
At Home Screen
Choose C

14. 𝒔𝒐 𝒕𝒉𝒆 𝒎𝒐𝒅𝒆𝒍 𝒊𝒔:
𝒚=𝟏𝟔.𝟖∗ 𝐬𝐢𝐧 𝟎.𝟓𝒙−𝟐.𝟐 +𝟔𝟐.𝟕

15. The sine equation is stored in Y1.
Press GRAPH

16. Predictions and such. User your Model: Predictions:
What is the average maximum temperature on March 15?
In some businesses, AC is turned on when temperature is above 68 degrees. For what time interval is the AC most likely to be turned on?

17. AC will be on from Approx. April 24th to Sept 15.
On March 15, the temperature is approximately 56.6 degrees
AC will be on from Approx. April 24th to Sept 15.

18. Repeat the process:
A) Use Average Minimum temperatures;
Don’t erase your other information:
Use L1, L3, Plot 2 , Y2
B) Use Average Precipitation;
Don’t erase your other information… but turn them off.
Use L1, L4, Plot 3 , Y3

19. Homework Use the given data for: State a model for each city.
Salt Lake City
New York City
Vancouver, Canada
Buenos Aires, Argentina
State a model for each city.
According to the models, which city resembles Portland max. temp trend most closely?