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Topic: trigonometry - identities!
Monica
I've got an owie on my head :(
posted 10-22-2003 07:05:45 PM
code:

cosB cotB
---- - ---- = -cos^2 B cot^2 B
secB tanB

wtfux! WTF WTF WTF!

i will never make it out of this class alive.

[ 10-22-2003: Message edited by: Monica ]

nem-x
posted 10-22-2003 07:07:54 PM
Aaaaaaaaaaaaaaaaaaaaaahahahahahhaahhahahahahahahhahahahahahhahaha
I remember having to do those stupid postulates/theorems and proofs.

sux2bu!

Monica
I've got an owie on my head :(
posted 10-22-2003 07:08:31 PM
quote:
nem-x had this to say about Captain Planet:
Aaaaaaaaaaaaaaaaaaaaaahahahahahhaahhahahahahahahhahahahahahhahaha
I remember having to do those stupid postulates/theorems and proofs.

sux2bu!


YOU WANNA TAKE THIS OUTSIDE?

Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 07:11:02 PM
No, wait, left side.

cos^2 - cot^2 = cos^2 - cos^2/sin^2 = (cos^2sin^2 - cos^2)/sin^2 = (cos^2(sin^2-1))/sin^2 = -cos^4/sin^2 = -cos^2cot^2

[ 10-22-2003: Message edited by: Oscar 3/Xray 1 ]

[b].sig removed by Mr. Parcelan[/b]
Chalesm
There is no innuendo in this title.
posted 10-22-2003 07:12:54 PM
Just remember (in general) when looking to deal with these kinds of things, make them all sines and cosines. Nine times out of ten, that will take it down to a simpler relationship. And sin^2 + Cos^2 =1. With those two rules, you should be able to simplify and/or prove just about anything.

[ 10-22-2003: Message edited by: Chalesm ]

In the beginning the Universe was created.
This has made a lot of people angry and been widely regarded as a bad move.

Douglas Adams, 1952-2001

Monica
I've got an owie on my head :(
posted 10-22-2003 07:15:07 PM
quote:
Chalesm had this to say about Reading Rainbow:
Just remember, make them all sines and cosines.

I TRIED THAT ALREADY.

Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 07:16:26 PM
quote:
Monica had this to say about Matthew Broderick:
I TRIED THAT ALREADY.

Read edit.

[b].sig removed by Mr. Parcelan[/b]
Alidane
Urinary Tract Infection
posted 10-22-2003 07:18:21 PM
Be content in the knowledge that you're probably never going to have to do these ever again.

Trying it now, though...k, beaten. Nice.

[ 10-22-2003: Message edited by: Alidane ]

Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 07:19:13 PM
quote:
Alidane had this to say about Robocop:
Be content in the knowledge that you're probably never going to have to do these ever again.

Trying it now, though..


I love these, actually.

I love trig integrals, too. Trig in its proofy form is one of my favorite subjects, though trig in its number form tries on my patience very fast.

[b].sig removed by Mr. Parcelan[/b]
Chalesm
There is no innuendo in this title.
posted 10-22-2003 07:22:15 PM
After that, you should often get everthing out of the denominator. In this case, you should find a cos^2 multipling everthing. If it's on both sides, it's nice and easy to get rid of, leaving good old sin^2 and Cos^2

(though since weis already solved it, I doubt you need my advice here)

To show how I did it, because it's a good general method

after sticking in sins and cosines

cos^2-(cos/sin)/(sin/cos) = -cos^4/sin^2

cos^2 -cos^2/sin^2=-cos^4/sin^2

so, getting the sin^2 out of the denominator

sin^2*cos^2-cos^2=cos^4

and divinding everything by cos^2 (since it's in everything)

sin^2+cos^2=1

that's the lovely thing and horribile thing about trig. There are a billion methods

[ 10-22-2003: Message edited by: Chalesm ]

In the beginning the Universe was created.
This has made a lot of people angry and been widely regarded as a bad move.

Douglas Adams, 1952-2001

Mortious
Gluttonous Overlard
posted 10-22-2003 07:22:32 PM
quote:
Oscar 3/Xray 1 had this to say:
I love these, actually.

I love trig integrals, too.


Burn in hell.

Alidane
Urinary Tract Infection
posted 10-22-2003 07:25:54 PM
quote:
Oscar 3/Xray 1 attempted to be funny by writing:
I love these, actually.

I love trig integrals, too. Trig in its proofy form is one of my favorite subjects, though trig in its number form tries on my patience very fast.


Bah. Proofs are just too abstract for me...it's all twiddling expressions and I never feel like I go anywhere.

But then, I can say that about most math...I mean...rotational solids? Infinite sets? Useful, yea...when hell freezes over.

[ 10-22-2003: Message edited by: Alidane ]

Chalesm
There is no innuendo in this title.
posted 10-22-2003 07:33:02 PM
I love math, but unfortunately I've learned from experience that my mind just can't follow it's pure, abstract form past a certain level. I need examples and applicable cases to really get a sense for what's going on, and pure math just doesn't offer that.
In the beginning the Universe was created.
This has made a lot of people angry and been widely regarded as a bad move.

Douglas Adams, 1952-2001

Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 07:36:49 PM
Chalesm, most teachers will not let you do that in proofs with trig when you start. They restrict you to only do operations to one side.

And the reason I'm starting to like these, I think, is because I can see right through the contrivances. Most of these problems are so obviously constructed to be in a math book. As a result, they follow certain patterns and common methods. Just as humans each have standard vocabulary that gets used over and over, math teachers have standard math "methods" that appear over and over in problems like these.

[ 10-22-2003: Message edited by: Oscar 3/Xray 1 ]

[b].sig removed by Mr. Parcelan[/b]
Naimah
In a Fire
posted 10-22-2003 07:39:47 PM
quote:
Alidane had this to say about Cuba:
Bah. Proofs are just too abstract for me...it's all twiddling expressions and I never feel like I go anywhere.

But then, I can say that about most math...I mean...rotational solids? Infinite sets? Useful, yea...when hell freezes over.


Engineering makes use of most things.

diadem
eet bugz
posted 10-22-2003 08:00:49 PM
quote:
When the babel fish was in place, it was apparent Monica said:
code:

cosB cotB
---- - ---- = -cos^2 B cot^2 B
secB tanB

wtfux! WTF WTF WTF!

i will never make it out of this class alive.


I know. It sucks. It's annoying and requires a lot of seemingly meaningless memorization. Problem is, you gotta learn it. Only real way to do it is keep at it until you got it. Use flashcards or whatever is best for you if you have to, but it's something you just gotta do.

Think of it as learning to use a hammer. It's painful to learn, but you can't really build much without knowing how to use it. You are learning how to use essential tools. Once you are finished with the annoying part, and believe me, this is it, you will be glad you spent the time to learn it.

play da best song in da world or me eet your soul
Monica
I've got an owie on my head :(
posted 10-22-2003 08:06:19 PM
bah

cos/(sec+tan) = 1 - sin
cos^2/tan
cos^2 sin/cos
cos sin

whawhawhaT

Monica
I've got an owie on my head :(
posted 10-22-2003 08:08:35 PM
quote:
diadem's unholy Backstreet Boys obsession manifested in:
I know. It sucks. It's annoying and requires a lot of seemingly meaningless memorization. Problem is, you gotta learn it. Only real way to do it is keep at it until you got it. Use flashcards or whatever is best for you if you have to, but it's something you just gotta do.

Think of it as learning to use a hammer. It's painful to learn, but you can't really build much without knowing how to use it. You are learning how to use essential tools. Once you are finished with the annoying part, and believe me, this is it, you will be glad you spent the time to learn it.


i'm trying to figure out HOW to do this, not why you think i should.

Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 08:20:58 PM
quote:
Monica had this to say about Optimus Prime:
bah

cos/(sec+tan) = 1 - sin
cos^2/tan
cos^2 sin/cos
cos sin

whawhawhaT


Heh, you didn't multiply the cos all the way through (or rather, treated addition like multiplication). cos(sec+tan)=1+sin. cos^2 is 1-sin^2 or (1-sin)(1+sin). Cancel (1+sin)s.

[ 10-22-2003: Message edited by: Oscar 3/Xray 1 ]

[b].sig removed by Mr. Parcelan[/b]
Monica
I've got an owie on my head :(
posted 10-22-2003 08:45:58 PM
but... it's cos DIVIDED by (sec+tan)....

why cos(sec+tan)...

Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 08:48:33 PM
quote:
Monica thought about the meaning of life:
but... it's cos DIVIDED by (sec+tan)....

why cos(sec+tan)...


Didn't you multiply top and bottom by cos?

[b].sig removed by Mr. Parcelan[/b]
Naimah
In a Fire
posted 10-22-2003 09:05:42 PM
code:

cosB cotB
---- - ---- = -cos^2 B cot^2 B
secB tanB


|||||||||||||||||||||||||||||||||||||


cos^2 B - cot^2 B = -cos^2 B cot^2 B


|||||||||||||||||||||||||||||||||||||


cos^2 B cos^2 B
cos^2 B - ------- = -cos^2 B -------
sin^2 B sin^2 B


|||||||||||||||||||||||||||||||||||||


( 1 ) cos^2 B
cos^2 B ( 1 - ------- ) = -cos^2 B -------
( sin^2 B ) sin^2 B


|||||||||||||||||||||||||||||||||||||


( 1 ) -cos^2 B
( 1 - ------- ) = --------
( sin^2 B ) sin^2 B


|||||||||||||||||||||||||||||||||||||


sin^2 B - 1 = -cos^2 B


|||||||||||||||||||||||||||||||||||||


1 - sin^2 B = cos^2 B


|||||||||||||||||||||||||||||||||||||


sin^2 B + cos^2 B = 1


That is it step by step. If you still don't get it then you will never get it.

Edit: Tried to improve formatting.

[ 10-22-2003: Message edited by: Naimah ]

Monica
I've got an owie on my head :(
posted 10-22-2003 09:19:51 PM
um

sec= 1/cos
tan= sin/cos

cos/(1/cos + sin/cos)

multiply the top and bottom by cos...

cos^2/(1 + sin)

ah HA

...

Monica
I've got an owie on my head :(
posted 10-22-2003 09:20:53 PM
quote:
Naimah spewed forth this undeniable truth:
code:

cosB cotB
---- - ---- = -cos^2 B cot^2 B
secB tanB


|||||||||||||||||||||||||||||||||||||


cos^2 B - cot^2 B = -cos^2 B cot^2 B


|||||||||||||||||||||||||||||||||||||


cos^2 B cos^2 B
cos^2 B - ------- = -cos^2 B -------
sin^2 B sin^2 B


|||||||||||||||||||||||||||||||||||||


( 1 ) cos^2 B
cos^2 B ( 1 - ------- ) = -cos^2 B -------
( sin^2 B ) sin^2 B


|||||||||||||||||||||||||||||||||||||


( 1 ) -cos^2 B
( 1 - ------- ) = --------
( sin^2 B ) sin^2 B


|||||||||||||||||||||||||||||||||||||


sin^2 B - 1 = -cos^2 B


|||||||||||||||||||||||||||||||||||||


1 - sin^2 B = cos^2 B


|||||||||||||||||||||||||||||||||||||


sin^2 B + cos^2 B = 1


That is it step by step. If you still don't get it then you will never get it.

Edit: Tried to improve formatting.


omfg i am so not talking to you go away h8 h8 h8

Agent A
Underpowered on Purpose
posted 10-22-2003 09:22:29 PM
Como what?

btw, the answer is 3.

"How do you all feel about beastiality with taxidermy? It seems like most people aren't very down with it, in fact, alot of people are only medium down with it. But if you only get to second base, where's the harm, right?"
- Melora Creager
Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 09:24:48 PM
quote:
There was much rejoicing when Monica said this:
um

sec= 1/cos
tan= sin/cos

cos/(1/cos + sin/cos)

multiply the top and bottom by cos...

cos^2/(1 + sin)

ah HA

...


Hehe, my teacher this year will put "WTH!" on tests for errors like that where you mess up early and then try to go on solving it.

The first time I saw that, I was very offended. Then I found out it stands for "Working too hard!". haha

[b].sig removed by Mr. Parcelan[/b]
Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 09:25:36 PM
code:

cosB cotB
---- - ---- = -cos^2 B cot^2 B
secB tanB


|||||||||||||||||||||||||||||||||||||


cos^2 B - cot^2 B = -cos^2 B cot^2 B


|||||||||||||||||||||||||||||||||||||


cos^2 B cos^2 B
cos^2 B - ------- = -cos^2 B -------
sin^2 B sin^2 B


|||||||||||||||||||||||||||||||||||||


( 1 ) cos^2 B
cos^2 B ( 1 - ------- ) = -cos^2 B -------
( sin^2 B ) sin^2 B


|||||||||||||||||||||||||||||||||||||


( 1 ) -cos^2 B
( 1 - ------- ) = --------
( sin^2 B ) sin^2 B


|||||||||||||||||||||||||||||||||||||


sin^2 B - 1 = -cos^2 B


|||||||||||||||||||||||||||||||||||||


1 - sin^2 B = cos^2 B


|||||||||||||||||||||||||||||||||||||


sin^2 B + cos^2 B = 1


That is it step by step. If you still don't get it then you will never get it.

Edit: Tried to improve formatting.[/qb]<HR></BLOCKQUOTE>

You are so 2 hours ago.

[ 10-22-2003: Message edited by: Oscar 3/Xray 1 ]

[b].sig removed by Mr. Parcelan[/b]
Monica
I've got an owie on my head :(
posted 10-22-2003 09:26:36 PM
quote:
ACES! Another post by Oscar 3/Xray 1:
Hehe, my teacher this year will put "WTH!" on tests for errors like that where you mess up early and then try to go on solving it.

The first time I saw that, I was very offended. Then I found out it stands for "Working too hard!". haha


my teacher is a freak. for this assignment he put pg143 1-5, 6-10, 11-15, 16-20 down on our assignment sheets.

and he once drew teeth on a Trig function because he thought it resembled Jaws.

at least i knew i had fucked up, right?

Demos
Pancake
posted 10-22-2003 09:28:21 PM
Now that our brains are fried, get a graphic calculator. Plug those identities in for future reference. Then proceed to setup programs to do stuff like the Laws of Sines and Cosines, etc for you.
"Jesus saves, Buddha enlightens, Cthulhu thinks you'll make a nice sandwich."
Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 09:29:39 PM
quote:
The logic train ran off the tracks when Demos said:
Now that our brains are fried, get a graphic calculator. Plug those identities in for future reference. Then proceed to setup programs to do stuff like the Laws of Sines and Cosines, etc for you.

Get out of my sight, heathen!

[b].sig removed by Mr. Parcelan[/b]
Monica
I've got an owie on my head :(
posted 10-22-2003 09:31:17 PM
quote:
ACES! Another post by Demos:
Now that our brains are fried, get a graphic calculator. Plug those identities in for future reference. Then proceed to setup programs to do stuff like the Laws of Sines and Cosines, etc for you.

and then get a 0 on my test as we are not allowed to use such evil devices during them.

well, mostly just for this chapter.

[ 10-22-2003: Message edited by: Monica ]

Demos
Pancake
posted 10-22-2003 09:36:07 PM
Darn...some teachers will look to see if you have programs, so I'd normally make an innocuous looking program that had commented-out formulae about 80 lines down..........
"Jesus saves, Buddha enlightens, Cthulhu thinks you'll make a nice sandwich."
Monica
I've got an owie on my head :(
posted 10-22-2003 10:33:52 PM
1/(tan+cot) = sin cos

... could i just... flip that, sorta? i mean, since they're inverses of each other and all...

like

cot+tan
cos/sin + sin/cos

... well damn it. this sucks. i can figure out why you get the answers you do, but i can't have any of the hard ones for myself. *sigh* been bouncing between the last 3 problems all night.

Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 10:40:26 PM
Your main task is to get rid of denominators and especially denominators within denominators. That usually works for me.

Multiply by the Least Common Denominator of tan and cot (because they're dirty denominators within denominators! dirty!) , sin*cos. (sin*cos * 1)/(sincos(sin/cos) + sincos(cos/sin)) = sin*cos/(sin^2 + cos^2) = sincos/1

Always try multiplying things first. A lot of these are hinged on multiplying top and bottom by the same thing.

[ 10-22-2003: Message edited by: Oscar 3/Xray 1 ]

[b].sig removed by Mr. Parcelan[/b]
Lyinar Ka`Bael
Are you looking at my pine tree again?
posted 10-22-2003 11:07:27 PM
What parts are you still having trouble with, Klo?


Lyinar Ka`Bael, Piney Fresh Druidess - Luclin

MorbId
Pancake
posted 10-22-2003 11:10:04 PM
quote:
Demos probably says this to all the girls:
Darn...some teachers will look to see if you have programs, so I'd normally make an innocuous looking program that had commented-out formulae about 80 lines down..........

Isn't it easier just to learn the formulas and procedures?

Ares
posted 10-22-2003 11:10:07 PM
The horror! The memories! ;___________;

New curriculum made me learn trig before my sister did.. And she 2 years older.

No more math for me! >

Naimah
In a Fire
posted 10-22-2003 11:14:02 PM
quote:
Oscar 3/Xray 1 had this to say about Tron:

You are so 2 hours ago.


Yea, but mine was pretty.

Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 11:14:20 PM
quote:
Captain MorbId had this to say about Punky Brewster:
Isn't it easier just to learn the formulas and procedures?

That's what I was thinking.

[b].sig removed by Mr. Parcelan[/b]
Snugglits
I LIKE TO ABUSE THE ALERT MOD BUTTON AND I ENJOY THE FLAVOR OF SWEET SWEET COCK.
posted 10-22-2003 11:14:57 PM
quote:
Naimah had this to say about Robocop:
Yea, but mine was pretty.

Pretty ugly, plus, like I said, most teachers want operations on one side only. You did two sides. You lose.

[ 10-22-2003: Message edited by: Oscar 3/Xray 1 ]

[b].sig removed by Mr. Parcelan[/b]
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