Question

The exact value of sin 5pi/12 is:

Answer 1

is it 0.97

Answer 2

hint:

\[\Large \frac{5\pi}{12} = \frac{1}{2}*\frac{5\pi}{6}\]

Answer 3

You'll use the half angle formula

Answer 4

they want an exact value (not an approximation)

Answer 5

So I guess I can eliminate a. and d.

Answer 6

doesn't 1/2 * (5pi/6) = 1.30

Answer 7

you'll use this

http://1.bp.blogspot.com/_22SNRpx_D5A/TQlI4UzME3I/AAAAAAAAAAs/HWHHmtVcLiM/s320/eq5.gif

Answer 8

in this case, u = 5pi/6

Answer 9

@jim_thompson5910 I think I got it. It is b. √2(√3+1)/4

Answer 10

yep, it's B, you can also use a calc to see that

sin(5pi/12) = 0.96592582628907
(sqrt(2)*(sqrt(3)+1))/4 = 0.96592582628907

since they yield the same approx result, the two are equal