Register to reply

Trigonometric functions of the unit cirlce..

by AznBoi
Tags: cirlce, functions, trigonometric, unit
Share this thread:
AznBoi
#1
Dec12-06, 06:35 PM
P: 471
I just came across a problem that wants you to solve for csc of an angle in radians... However, I'm confused about the answer given.

Here is the problem:

Find the csc when t=-2pi/3, which is equivalent to -120 degrees right?

I got -2sqrt.(3)/3 but the answer in the back is -2sqrt.(3)/2 Why is it a 2 instead of a three??

The sin is -sqrt.(3)/2 and it is correct, so shouldn't the csc be the reciprocal of sin?? 1/sin theta?? so 1/(-2sqrt.(3)/3)????????

Thanks!
Phys.Org News Partner Science news on Phys.org
NASA team lays plans to observe new worlds
IHEP in China has ambitions for Higgs factory
Spinach could lead to alternative energy more powerful than Popeye
cristo
#2
Dec12-06, 06:53 PM
Mentor
cristo's Avatar
P: 8,305
Your book is wrong. [tex] cosec(\frac{-2\pi}{3}) = \frac{-2\sqrt{3}}{3} [/tex]
AznBoi
#3
Dec12-06, 06:58 PM
P: 471
wow... I think I've actually seen quite a few with 2's as the denominator. I'm pretty sure that I was right and the book was wrong. I'm astonished though, this book sucks! =/


Thanks for helping me check btw!! =]


Register to reply

Related Discussions
Trigonometric Functions And Identities General Math 5
Trigonometric functions and radians Calculus & Beyond Homework 2
Trigonometric Functions..simplify sin squared functions Precalculus Mathematics Homework 2
Trigonometric Functions Precalculus Mathematics Homework 5
Trigonometric Functions Graphing Introductory Physics Homework 2