Posted by **Edan** on Thursday, November 5, 2009 at 6:38pm.

1.Using exact values, verify that

cos 60°=1-2 sin² 30°

- Trigonometry -
**bobpursley**, Thursday, November 5, 2009 at 6:47pm
I am not certain what I am seeing.

Is it

cos^2 60=1-2sin^2 30 ?

3/4=?=1-2*1/4

so it doesn't verify...so I must not be seeing the type clearly

- Trigonometry -
**Edan**, Friday, November 6, 2009 at 12:01am
This is exacly how the question goes, This is a test question.

1.Using exact values, verify that

cos 60°=1-2 sin² 30°

## Answer this Question

## Related Questions

- MATH - 1.)Find the exact solution algebriacally, if possible: (PLEASE SHOW ALL ...
- tigonometry - expres the following as sums and differences of sines or cosines ...
- math - Use the exact values of the sin, cos and tan of pi/3 and pi/6, and the ...
- math - Use the exact values of the sin, cos and tan of pi/3 and pi/6, and the ...
- math - use exact values of the sin,cos and tan of (pi/3) and (pi/6)(which I have...
- trigonometry - Verify that following are identities: 1. cos 3t = 4 cos³ t-3 cos ...
- Trig (math) - 1.) Write the complex number in trigonometric form r(cos theta + i...
- math - use exact values of the sin,cos and tan of (pi/3) and (pi/6)(which I ...
- Trigonometry/ Please Help - Find two exact values of sin(cosˉ¹√5/6)
- Math- Trig - 1. Determine the exact value of cos^-1 (pi/2). Give number and ...