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[url=http://i.imgur.com/USZS6F5.png]If someone hasn't[/url]?
[url=http://i.imgur.com/1ilcv8d.png]Also in case someone hasn't done this one either haha[/url].

My computer is freezing

PM'ed u Symphs

@Avatar:

So... Maximum to max, and min to min.

:I

Such fancy terms.

And sorry, i'm having a tough time trying to draw it out.

Can you assist me? https://awwapp.com/draw.html#e3684a3e

[quote=Symphs]I'm sorry, but what is a crest to crest and trough to trough?

@CIeavage

Wow, thank you for the response! But, you lost me at the 1+tan0/1+tan0 part. Where did those come from?[/quote]

You don't know what crest and trough mean? That is strange. The crest is the highest point in a wave so it is the peak in a sine wave and a trough refers to the minimum point of the sine curve. If you were to put your finger on a sine graph and move your finger along the path of the curve, the period is the distance between the two points where your finger repeats itsself. For example going from the maximum of a sine curve back to the maximum, minimum to minimum or any two points where your finger has the same motion. You know at what time the maximum is and what time the minimum is so you can find the distance between the maximum and the minimum. If you multiply that number by 2 you will find the distance from maximum to minimum to maximum again (or the period).

[quote=Symphs]Haha, yeah... BUT THAT -1/3 DOE[/quote]

Hmm, i guess you're right about it not being part of a special triangle. If you really want an exact value i suppose you could put
pi - cos^-1(1/3) + n(2pi) and pi + cos^-1(1/3) + n(2pi) where n is an integer (since you're solving over all reals) as an answer, but i think 1.91 + n(2pi) and 4.37 + n(2pi) would suffice.

[quote=CIeavage]Np, i skipped a few steps so its nice to see you can follow it
Hopefully someone else can explain #3,4 i'm too tired o.o[/quote]

Haha, yeah... BUT THAT -1/3 DOE

[quote=Symphs]Oh my god. WOW. I completely did not see the two in the tan. I'm sorry.

Thank you.[/quote]

Np, i skipped a few steps so its nice to see you can follow it
Hopefully someone else can explain #3,4 i'm too tired o.o

[quote=CIeavage]For the numerator, i multiplied it with (1 - tan0), which gave me (1 - tan^2(0))
ie. (1 - tan0)(1 + tan0) = (1 - tan^2(0))
(x - y)(x + y) = (x^2 - y^2)[/quote]

Oh my god. WOW. I completely did not see the two in the tan. I'm sorry.

Thank you.

[quote=Symphs]I see your strategy there, but when you multiplied that value in. You took the denominator but completely ignored the numerator? [/quote]

For the numerator, i multiplied it with (1 - tan0), which gave me (1 - tan^2(0))
ie. (1 - tan0)(1 + tan0) = (1 - tan^2(0))
(x - y)(x + y) = (x^2 - y^2)

[quote=CIeavage](1+tan0)/(1+tan0) is another form of 1 (think of like 7/7), so multiplying the expression by 1 doesn't change it
For solving identities, a good strategy is to make one side look like the other side, so multiply by that allows me to get (1+tan0) in the denominator [/quote]

I see your strategy there, but when you multiplied that value in. You took the denominator but completely ignored the numerator?

Also, how do you solve for -1/3. It's not one of our special triangles so...

[quote=Symphs]@CIeavage

Wow, thank you for the response! But, you lost me at the 1+tan0/1+tan0 part. Where did those come from?[/quote]

(1+tan0)/(1+tan0) is another form of 1 (think of like 7/7), so multiplying the expression by 1 doesn't change it
For solving identities, a good strategy is to make one side look like the other side, so multiply by that allows me to get (1+tan0) in the denominator

[quote=Avatar]The period is the distance from one point to an equivalent point one phase later in the repetition pattern. So this can be crest crest or trough to trough or midpoint to midpoint. So you are given the time from a crest to a trough take that time and add it again to find the period (crest to crest).[/quote]

I'm sorry, but what is a crest to crest and trough to trough?

@CIeavage

Wow, thank you for the response! But, you lost me at the 1+tan0/1+tan0 part. Where did those come from?

[quote=Symphs]Yes there is.

So, the question is.

A tidal wave hits a max height of 10.8 at midnight, a minimum height of 5.8 feet at 9 am. Find the height of the wave at 7 am.

Assuming the relationship is sinosudial, I got the midline (2.5) , but I dont know how to find the period, so I can solve for a[/quote]

The period is the distance from one point to an equivalent point one phase later in the repetition pattern. So this can be crest crest or trough to trough or midpoint to midpoint. So you are given the time from a crest to a trough take that time and add it again to find the period (crest to crest).

[quote=Avatar]Are there any word problems? I might be able to help but cant click links right now sorry [/quote]

Yes there is.

So, the question is.

A tidal wave hits a max height of 10.8 at midnight, a minimum height of 5.8 feet at 9 am. Find the height of the wave at 7 am.

Assuming the relationship is sinosudial, I got the midline (2.5) , but I dont know how to find the period, so I can solve for a

Q1)Going to replace theta with x cause i don't have the symbol
Note that sin^2 = (1-cos^2), so apply substitution
3(1 - cos^2(x)) + 5cosx = 1
3cos^2(x) - 5cosx - 2 = 0
if you want you can let y = cosx and you'll get
3y^2 - 5y - 2 = 0
(3y + 1)(y - 2)
So resub and you get cosx = -1/3 and cosx = 2
Reject cosx = 2 since its domain is [1,1]
In the end just solve for cosx = -1/3

Q2) http://i.imgur.com/2qAu94R.png
If it seems like its incomplete, note that cos^2(x) - sin^2(x) = cos(2x) (double identity)

Ugh, I just realized I'm gonna completely forget all this over the summer even though I learned it last year. Probably because I [i]barely[/i] understood it this year.

Are there any word problems? I might be able to help but cant click links right now sorry

[quote=Iwantodrawnowhu]the 3% of basilers that answer these question probably will chose not to because there is no direct link[/quote]

http://oi60.tinypic.com/29cuxef.jpg

the 3% of basilers that answer these question probably will chose not to because there is no direct link