## kenneyfamily 3 years ago write an equation of a sine function with amplitude 3, period 3pi/2 and phase shift pi/4

1. kenneyfamily

is it y=3sin(3x/2-pi/4)?

2. AERONIK

3sin((4/3)t+(pi/4))

3. kenneyfamily

4. AERONIK

general equation of a simple harmonic oscillator is Asin(wt). where A is the amplitude and w is the angular frequency.. amd 2pi/w is the time period...

5. AERONIK

the equation you are giving should be a function of time and not distance... and by adding a minus sign you are just changing its phase by pi.

6. kenneyfamily

7. kenneyfamily

a. y = -3 sin (3x/2 - 3π/8) b. y = 3 sin (4x/3 - π/3) c. y = -3 sin (4x/3 - π/4) d. y = 3 sin (3x/2 - π/4)

8. kenneyfamily

those are my choices @AERONIK

9. AERONIK

you got me wrong friend, your choices are definitely correct....

10. kenneyfamily

wait i'm confused

11. zepdrix

$\huge y=a \sin(bx-c)+d$$a=amplitude$$\frac{2\pi}{b}=period$$c=phase \; shift$

12. zepdrix

Let's figure out our b term. $\large \frac{2\pi}{b}=\frac{3\pi}{2}$$\large b=\frac{4}{3}$ I hope I calculated that correctly hehe

13. zepdrix

$\large y=3\sin\left(\frac{4}{3}x-\frac{\pi}{4}\right)$

14. zepdrix

Mmmmm I'm not sure if I did that correctly, was I suppose to factor the 4/3 into the pi/4? I forget...

15. kenneyfamily

thats not an option :(

16. zepdrix

Hmm

17. kenneyfamily

wait yes i think so

18. zepdrix

Yah I think the b is suppose to be like this... $\huge y=a \sin (b(x-c))+d$

19. zepdrix

Which IS one of your options, if you distribute the 4/3 to the pi/4 term.

20. zepdrix

21. kenneyfamily

i think its b. y = 3 sin (4x/3 - π/3)

22. zepdrix

Hmmm I think so too :O