# Algebra II

posted by .

Find the exact value of cos 375 degrees.

Is this correct?

• Algebra II -

15 deg
sin (30/2)= sqrt [(1-cos 30)/2 ]
cos 30 = sqrt 3 /2
sqrt [ (1- sqrt 3/2)/2]
sqrt [ (2 - sqrt (3) ) /4 ]
= (1/2) sqrt (2 - sqrt 3)

## Similar Questions

1. ### Algebra

1)A bookshelf holds 4 mysteries, 3 biograpghies, 1 book of poetry, and 2 reference books. If a book is selected at random from the shelf, find the probability that the book selected is a biography or reference book. A)1/2 B)1/6 C)5/6 …
2. ### Math

1)Find the standard deviation of the data set to the nearest tenth. (21,13,18,16,13,35,12,8,15) A)16.8 B)7.8 C)7.3 D)5.7 I chose C mean = 21+13+18+16+13+35+12+8+15/9 16.8 variance = (21-16.8)^2 = 17.64...did that with the rest and …
3. ### Algebra II

Find the exact value of sin(theta/2) if cos theta = 2/3 and 270 degrees<theta<360 degrees. Answer: sqrt6/6
4. ### Algebra II

1)Find the exact value of sin 165 degrees. Answer: (sqrt6 + sqrt2)/4 2) Simplify: (4m/5n^2)- (n/2m) Answer: (8m^2-5n^3)/10n^2m Thanks
5. ### Algebra II

1)Find the exact value of sin 165 degrees. Answer: (sqrt6 + sqrt2)/4 2) Simplify: (4m/5n^2)- (n/2m) Answer: (8m^2-5n^3)/10n^2m Thanks

Use a sum or difference identity to find the exact value of sin 255 degrees Answer: sqrt6-sqrt2/4 Thanks
7. ### Algebra II

Multiple Choice (theta) means the symbol 0 with the dash in it. 1.)Which expression is equivalent to tan(theta)-(sec(theta))/(sin(theta))?
8. ### Trigonometry (Help and Check)

Evaluate (exact answers): a) sin^-1(cos30) Need help. What do I do?