Question

Can anyone explain Trigonometric Identities and how they work?

Answer 1

I understand this http://www.sosmath.com/trig/Trig5/trig5/trig5.html
But I'm not sure how it all works. :/ Can anyone give me an example on how Trigonometric Identities work, and why they're used?
Thanks! :)

Answer 2

Which ones do you want to be explained?

Answer 3

Just how it all works. I know it sounds stupid, but I don't understand Trigonometric Identities at all.

Answer 4

do you know what the unit circle is?

Answer 5

That I know! :)

Answer 6

ok woops i put x-axis on both :(

but

you should start with the simplest ones

which are

the first ones on your webpage.

sin u=1/csc u
cos u=1/sec u
tan u=1/tan u

Answer 7

i mean tan u=1/cot u

Answer 8

those you can just memorize because secant, cosecant, and cotangent were created just for an easy way to do reciprocals on sines, cosines, and cotangent.

Answer 9

I have those memorized, but It's just, why do we need them?

Answer 10

it's for easy reciprocalizing for harder math

Answer 11

please wait, i need to draw something for pythagorean identities

Answer 12

Ahhhh okay, xD I'll be here! :) Take your time.

Answer 13

The trig functions are periodic wave functions.
They can be used to model tons of different natural phenomena like sound waves.

And yah, as rrrr is mentioning, they help us relate angles and side lengths of triangles.
fun stuff :D

I always find it hard to answer such a question because I'm a math geek.
I love love love trig functions.
But I hardly ever think about their actual use XD lolol

Answer 14

See, I'm not a Math Geek, so it's harder for me to understand it. :/ But I'm a History Nerd. :P

Answer 15

OHHHHH Rrrr your little drawing thing just made me understand something. o_O

Answer 16

I think it's slowly starting to make sense. Thanks you guys/gals! :)

Answer 17

i'm horrible at history :(

youre welcome

Answer 18

i'm trying to solve this problem

Given that sin(2θ)=2/3, the value of

sin^6(θ)+cos^6(θ)

can be written as a/b with a and b coprime positive integers. Find a+b.

Answer 19

you might want to try out

brilliant.org

it's where this problem came from

wait... do you have a facebook?

Answer 20

I don't give out my information, that includes facebook, sorry! :) I'll try it out though.

Answer 21

umm...because if I refer you(send u an email, such) I get extra problems!

so yes :)

Answer 22

and you can only sign up with facebook for me to get extra problems :( thats the bad thing about Brilliant is that it's too facebook-related :(

Answer 23

here is the link

you don't have to tell me anything :)

just sign up it's a math and physics website, really fun, you can earn points to get good stuff such as t-shirts!!!

http://brilliant.org/invite/bON5EL2PjmSUt/