Question

How to evaluate CSC(15deg) without using a calculator? Thanks.

Answer 1

by using the identities


csc(theta) = 1/sin(theta)

sin(A - B) = sin(A)*cos(B) - cos(A)*sin(B)

Answer 2

Sin(40-30) = (Sin(sqrt(2)/2) (Cos(sqrt(3)/2) - Cos(sqrt(2)/2) (Sin(1/2)
= sqrt(6) / 4 - sqrt (2) /4
= sqrt(6) - sqrt(2) / 4

Did I do this right? Thank you so much.

Answer 3

So it would be: ?

How do i simplyfy the fraction within the fraction?