Question

Need help!! Will medal and fan!!

Answer 1

The graph of the sine curve below is of electromagnetic energy that represents red light:

Answer 2

What function accurately represents the sine curve for red light?

Answer 3

And I have the answer choices:

f(x) = sin pi over 640x

f(x) = sin 640πx

f(x) = sin 320πx

f(x) = sin pi over 320x

Answer 4

Hey @Mehek14 can you help please?

Answer 5

Or @fairytail_lover

Answer 6

Or @nincompoop
@jigglypuff314
@mayankdevnani
@Preetha

Answer 7

Or @agent0smith
@welshfella

Answer 8

Or @ILovePuppiesLol
@just_one_last_goodbye
@sammixboo

Answer 9

Hey @agent0smith do you know how to do this?

Answer 10

First. Find the period from the graph

Answer 11

Then your function will be sin(bx)

where \[\large period = \frac{ 2\pi }{ b}\] solve for b

Answer 12

Is the answer sin320 pi x
(answer choice C)

Answer 13

Wait no, I think that's wrong :/ I'm confused

Answer 14

The period is 640, so 640= 2pi/b ... And then where do I go from there?

Answer 15

Well, you need b, so... :P

Answer 16

And I don't care what the answer choice is, just work out the correct function first

Answer 17

But what would the b be? It doesn't say anything about the b?

Answer 18

Solve for b. You have the equation for it above

Answer 19

I got about 4,021 :/

Answer 20

640= 2pi/b solve for b. Keep everything exact, ie leave pi as pi.

Answer 21

OHH, ok. Sooo 1,280 pi = b

Answer 22

No...

Answer 23

first cross multiply
640b = 2 pi

now what is b?

Answer 24

\[\large 640= \frac{ 2\pi }{ b}\]multiply both sides by b

Answer 25

Ok so 640b = 2 pi

Answer 26

What do I do next? Divide by 2?

Answer 27

You want to get b alone... so divide both sides by 640

Answer 28

Ohh, ok so b = 2 pi/ 640

Answer 29

But that's not an answer choice... what do I have to do next?

Answer 30

Oh wait, now that I have b I can plug it in the formula right?

Answer 31

So 640 = 2 pi/ (2 pi/ 640) ???

Answer 32

^nooooo

"Ohh, ok so b = 2 pi/ 640"

Simplify that first.

Then plug into sin(bx)

Answer 33

you can simplify 2 pi/640
divide top and bottom by 2.

Answer 34

Ok so pi/ 320

Answer 35

And now I have to do sin (pi/320) ?

Answer 36

I got 0.000171347

Answer 37

?

Answer 38

Noooooooo

"Then plug into sin(bx)"

You forgot the x.

Answer 39

theres no need to work out pi/320

just leave it like that

Answer 40

Ohhh, so is the answer D?
f(x) = sin pi/320 x

Answer 41

yea

Answer 42

YAY, thanks :)
Can you guys help me with another question? :/

Answer 43

I will be back in 20 minutes and will tag you in my question. THANKS! :)

Answer 44

I'll be gone by then, there's a fancy lunch that requires my eating skills

Answer 45

luck for some!! lol!

Answer 46

Yep it's an open bar too :D