posted by Carry .
i got totally the wrong answer how do i approach this?
That is pi/12 less than 2 pi (360 degrees), which would be 345 or -15 degrees. The sin of that angle is -0.2588
If you don't want the decimal approximation, it is
-sin(45 - 30) = -sin 45 cos 30 + sin 30 cos 45 = (sqrt 2)/2*[1/2 - (sqrt3)/2]
= (sqrt2)/4 -(sqrt6)/4
haha i got that too! but the right answer is
why don't you evaluate your "right" answer and compare it with drwls answer ?