Could you show me how to do these ?

' use even and odd properties of the trigonomic functions to find the exact value of the expression'

Sin(-π/6)


'Find the exact value'

Sec 60°





Thank for any help really they told me I could take pre calc or trig before calc I chose pre calc teacher then assumes we know trig and spends 10 min on it..

@ second one, use the unit circle.

http://www.youtube.com/watch?v=T9iaBr-YV60

This post was edited by carteblanche on Mar 2 2014 12:37am

I thought about using unit circle but sec 60° is π/3 and sec is 1/x so sec is 1/π

But that's not right

Would sec 60° just be 2?

Sec = 1/x

Values for 60° are. ( 1/2, √3/2)

1/(1/2) = 2

YES ?

I think, for this you can just use Trig Identities.

Sin = b/h
Cos = a/h
tan= b/a

csc = h/b
Sec = h/a
cot = a/b

a = adjacent
b = opposite
h = hypotenuse

So, using the unit circle to find cos(60) = (1/2)
thus, Sec(60) = (2/1) = 2

If you struggle with Trig, just remember the phrase, Soh Cah Toa. Which means, Sin(S) equals the opposite(o) over hypotenuse(h), Cosine equals the adjacent over the hypotenuse, and Tangent equals the opposite over adjacent

The beginning of calc is all pre-algebra and trig which I hate, then you learn the limit definition which is the long way to taking a derivative and it's not too bad.
Once you start getting more in depth with calc 1 it turns into derivatives and integrals which is easy. Calc 2 is more complex and harder derivatives/integrals and then double integrals at the end of calc 2, then calc 3 turns into 3D which means triple integrals, cartesian vectors, dot product, cross product, spherical coordinates, cylindrical coordinates, etc, etc. I hated Calc 3 the most. Then if you make it as far as Diff EQ, it is completely different and isn't even related to calc really other than knowing how to compute derivatives and integrals.

You'll probably need to learn the unit circle, just learn the first quadrant and then you'll be able to relate that to the other quadrants.

This post was edited by cky24 on Mar 2 2014 11:08am

Ok thabks

This post was edited by fingerling on Mar 2 2014 01:42pm