1. 7.8 Sinusoidal Graphs

2. Graph of y = sinx Period = 2𝝅 Amplitude = max – min = 1 – – 1 = 1 2 2
x y 1 –1
Period = 2𝝅
Amplitude = max – min = 1 – – 1 = 1
2 2

3. General Sine Curve We’ll do c & d tomorrow
If a is (+), typical sine curve
If a is (–), reflect through x-axis

4. Ex 1) Graph y = 3sinx b = 1 c = 0 a = 3 d Amp = 3 Period = 2𝝅–3
Amp = 3
Period = 2𝝅
Increment length

5. Ex 2) Graph y = sin2x b c a d
= 2
= 0
= 1 1 –1
Amp = 1
Per:
IL:

6. Graph of y = cosx Period = 2𝝅 Amplitude = max – min = 1 – – 1 = 1 2 2
x y 1 –1
Period = 2𝝅
Amplitude = max – min = 1 – – 1 = 1
2 2

7. General Cosine Curve We’ll do c & d tomorrow
If a is (+), typical cosine curve
If a is (–), reflect through x-axis

8. Ex 3) Graph b = c = 0 a = –2 d Amp = 2 Per: IL:
a = –2  reflect across x-axis

9. Homework
#720 Pg – 4 all, 13 – 20 all