Homework Help: Trigonometry

Posted by Jennifer on Thursday, March 3, 2011 at 7:55pm.

use the appropriate trig identity (sum and difference, half angle, double angle) to find the exact value. 1)cos 255 degrees
2) sin 165 degrees
3) tan 285 degrees

Trigonometry - bobpursley, Thursday, March 3, 2011 at 7:58pm
isn't 255 = 180+75=270-15 which is 270-30/2?

isn't 165=180-30/2

isn't 285=270+30/2?

Answer this Question

Related Questions

MATH - 1.)Find the exact solution algebriacally, if possible: (PLEASE SHOW ALL ...
trigonometry - We begin by setting t=sin 18 degrees we weill think of t an an &...
TRIG/ALGEBRA - 1) Find the exact value. Use a sum or difference identity. tan (-...
Algebra 2 Honors - Find the exact value by using an appropriate sum or ...
trig - Find the exact value by using a half-angle identity. cos 22.5 degrees
Pre-Calculus-check answers - Use a sum or difference identity to find the exact ...
Math-Trigonometry - Use the half-angle formulas to find the exact values. Cosine...
trig - find the exact value by using the appropriate half-angle identity: sin(...
math - find the angle that is coterminal to 525 degrees and lies between 0 ...
Math - Use a double or half angle identity to find the exact value of the ...

For Further Reading

First Name:
School Subject:
Answer: