7.4 Graphing Sine (Digital Version)

Graphing the relationships of periodic functions.

• A relationship the repeats in the same pattern over the same amount of time.

• Years increase in numbers but repeat the same days.

• The clock repeats itself every hour but it does not stay the same time.

• Amplitude - identifies the highest and lowest output values.

• Midline - What the amplitude is centered around.

• Period - the interval of time that a relation takes to complete one cycle or rotation. Think a year here...the period would be 365 days.

• Find the highest y - output and the lowest output.

• Calculate the distance between the highest and lowest values.

• Divide it by two...this is the amplitude.

• (2 - (-2)) = 4...4/2 = 2. The amplitude is 2.

• You can start at one of three places; a highest point, a lowest point, or a zero.

• Find the x - value at that point. Let's start at the coordinate point (-3, 2) this would be a "highest point." The x - value is -3.

• Follow the function until you reach the SAME y - value that you started at. You will use that x - value as the ending point. The point (1, 2) would be the NEXT, same y - value. The x - value is 1.

• The distance between the x - values is the period.

• 1 - (-3) = 4; the period is 4 units.

• You can also simply count!