# Thread: Anyone good at math?

1. ## Anyone good at math?

using identities find the values
1. sin* = -6/7 , find cos*

2. sec^2 pie/12 - tan^2 pie/12

for # 2 i think you have to deo something with the equation cos^2 X = 1 - sin^2 X

Find exact value
3. cos* = -12/13 , angle (*) in quad III

4. Tan* = -3 , cos *>0

2. I remember that stuff, not enough to help though. I'm so glad they teach such useful things in school.

3. Do you just want exact answers? What do you mean by "cos*" ? What's the * for?

4. i'm not gonna look at all that

but uh

sohcahtoa

5. You spelled pi "pie". You do not deserve my assistance.

6. * = angle
sin angle = such and such

and pie/pi....its been a long day at school...project due tomorrow morning and teacher cant speak english or teach

7. Originally Posted by TOBART
What do you mean by "cos*" ? What's the * for?
Cosin
and as was stated * = the angle

8. Originally Posted by accuFLEX

using identities find the values
1. sin* = -6/7 , find cos*
Okay, well, if sin theta is negative, theta is in quadrant 3 or 4.

Constructing the reference triangle, the sides are as follows:

Opposite: 6
Hypoteneuse: 7

So, if theta is in quadrant 3, cos theta is negative sqrt(13)/7

If theta is in quadrant 4, cos theta is positive sqrt(13)/7

Originally Posted by accuFLEX

2. sec^2 pie/12 - tan^2 pie/12

for # 2 i think you have to deo something with the equation cos^2 X = 1 - sin^2 X
This is just the pythagorean identity. It is identically equal to one. You need to learn your identities.

Originally Posted by accuFLEX

Find exact value
3. cos* = -12/13 , angle (*) in quad III
Use cos theta = 12/13 to find the reference angle, then add it to 180 degrees

Originally Posted by accuFLEX

4. Tan* = -3 , cos *>0
Tan is negative in quadrants II and IV

If cos is positive, this eliminates quadrant II

Since tan theta = -3, the reference triangle has opposite = 3, adjacent = 1, hypoteneuse = sqrt(9+1) = sqrt(10)

Cos theta is adj/hyp, and positive.

9. E = MC^2

I win.

Really though....What are you taking? 0.o

10. Built...wow...you really do know everything

11. Originally Posted by accuFLEX
Built...wow...you really do know everything

12. Originally Posted by MM
So, you're saying that google is just Built in disguise?

13. Originally Posted by MM

haha no, shes a mathematician.. really..!

14. Originally Posted by galileo
You spelled pi "pie". You do not deserve my assistance.
BHWEHAHAHAHAHAHA

ahahahhahahahahahahaha

15. Originally Posted by accuFLEX
Built...wow...you really do know everything
Quoted!

16. Originally Posted by cosmicdebree88
So, you're saying that google is just Built in disguise?
Also quoted

17. Built, you're a mathmatician?

18. Ew, I hate being a geek. I started to work it out without thinking. Thanks for giving the answers and relieving me from doing it on my own, Built.

So, if I put questions about Linear Algebra up here next semester would you answer those too?

19. Use a calculator. Thats what they are for.

Seriously, if you are looking into a career that in anyway uses math, I would just bite the bullet and learn this stuff. Its soooo basic, that if you don't learn it now, when you get to the harder stuff, you'll never make it.

20. its easy to say "just learn it" but i have little to no notes on this stuff. My teacher cant speak english. I can post a sound clip of him if you want me to (just need to know where i can host it)

Are there any good sites for this type of math?

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