Question

Find the equation of a sine function that has a vertical displacement 2 units down, a horizontal phase shift 60° to the right, a period of 30°, a reflection in the y-axis and an amplitude of 3.

Answer 1

@callisto can you help here please?

Answer 2

Im working on it but Im not sure if its going the right path.
Could the end of the new equation be 2(x+30degrees)-2?

Answer 3

Could it be 3 sin (30(x)- 60) -2 ?

Answer 4

sine function -> y=sinx
vertical displacement 2 units down, => y = sinx -2
a horizontal phase shift 60° to the right -> y = sin(x-60) -2
period of 30° = 1/12 (360) -> y = sin(12x-60) -2
a reflection in the y-axis -> y = sin(-12x-60) -2 = -sin(12x+60)-2
an amplitude of 3 -> y=-3sin(12x+60)-2

Hmmm... I'm really not good at graphs :(

Answer 5

Thank you. I will just examine the graph:)

Answer 6

Hmm.. perhaps wolf helps? not sure though

Answer 7

Ok, so your graph does have the correct properties

Answer 8

The amplitude is 3

Answer 9

I understand most of the equation, but can you explain the period of 30° = 1/12 (360) -> y = sin(12x-60) -2 part?

Answer 10

Hmm.. since the period is 30, which is reduced by 1/12 of the original sine graph. Like the previous one, if you reduce by 1/2, you would write y=sin (2x). Now, it's 12, so, multiply x by 12. I think it would work... Not sure though :S

Answer 11

Hey, In the geogebra site, is there a way I can see degrees in the grid instead of numbers?