Posted by **Wes** on Thursday, April 22, 2010 at 8:54pm.

How do you express in terms of angles less than 90 degrees?

sin 120 degrees

cos 150 degrees

tan 280 degrees

- trig -
**Reiny**, Thursday, April 22, 2010 at 9:41pm
Always ask yourself,

1. What quadrant is the angle in? That determines the ± according to the CAST rul

2. "How far is it to the x-axis"?

sin 120° = sin60

cos150° = -cos 30

tan 280° = -tan 80°

- trig -
**victor_hery**, Friday, August 31, 2012 at 12:20am
Sin (180 - A) = sin A. (angle in degrees)

sin 120 = sin (180 - 60) = sin 60

Cos (180 - A) = - cos A

cos 150 = cos (180 - 30) = - cos 30

tan (360 - A) = - tan A,

tan 280 = tan (360 - 80) = - tan 80

## Answer this Question

## Related Questions

Math - How do you express in terms of angles less than 90 degrees? sin 120 ...

Trigonometry - Please review and tell me if i did something wrong. Find the ...

trig - I have to retype this. For which angles theta, with 0 degrees less than/...

math - For which angles beta, with 0 degrees less than/equal to beta less than/...

Trig - What is the exact value of cos 40 degrees cos 50 degrees minus sin 40 ...

Trig(continued) - 2)Find the solution of sin2 theta = cos theta if 0 -< theta...

Algebra II - Multiple Choice (theta) means the symbol 0 with the dash in it. 1.)...

trig - To the nearest degree, all of the following angles are solutions of the ...

trigonometry (please double check this) - Solve the following trig equations. ...

Math - 1. Find the value of Sin^-1(-1/2) a. -30 degrees b. 30 degrees c. 150 ...