# trigonometric functions

posted by
**Katrina**
.

im compeletely lost with the trigonometric functions...can anyone explain clearly to me?

Are you lost on the definitions?...where is the problem.

You need to be able to draw and label all the parts of a triangle, the hypotenuse and legs. Then be able to define sine, cosine, tangent, etc. After that you need to be able to identify identities and manipulate the trig functions.

You should be able to find plenty of sources to help to. Look at the jump box up above and find trignometry. There's plenty there to help you.

I need more specifics on your difficulties to continue here.

the problem is that..

i don't know what are sin, cos, and tan, and how to manipulate the trig functions

Be sure to check the jump box at the top. There is a trig section here. If you follow that link there is a page with a lot of trig exercises. The second section covers the definitions of the functions.

Sine is the ratio of a leg opposite an angle to the hypotenuse.

Cosine is the ratio of the leg adjacent to an angle to the hypotenuse.

Tangent is the ratio of ratio of a leg opposite an angle to the leg adjacent to the angle.

Check the site above and try some specific questions. Unfortunately this site is set up to help with homework, not for teaching. I'll do what I can to help you though.

sin can be written as y/r (r= radius)

cosine = x/r

tan= y/x

cosecant= r/y

secant= r/x

cotangent= x/y

as more of a definition, sin = opposite leg/hypotenus

cosine= adjacent leg/ hypotenuse

tangent= opposite leg/ adjacent

and cosecant is the inverse of sine, secant is the inverse of cosine, and cotangent is the inverse of tangent

Amiga, this is correct somewhat. But it is based on right triangles (x,y are right angles, and the lower definitions you gave are right triangles). But all angles have sin, cos, and tan functions whether or not they are in a triangle. But in a sense you are correct, a beginning student starts with the above. Thanks.

I need to learn to write algebraic expression that is equivalent to the expression...

sec[arcsin(x-1)]

I need to learn to write algebraic expression that is equivalent to the expression...

sec[arcsin(x-1)]

what are 2 equivalent statements on

sec15

cos80

csc70

and how do you get them??