the answer isn't 8-2root3 btw

Answer:
Step-by-step explanation:
16cos(30)-20sin(60) -8sin(90)
look at the pattern of the numerators Millie, you can remember all of the sin and cos functions at the special angles now. :)
sin(0) = 0 / 2
sin(30) = 1 / 2
sin(45) = [tex]\sqrt{2}[/tex] / 2
sin(60) = [tex]\sqrt{3}[/tex] / 2
sin(90) = [tex]\sqrt{4}[/tex] / 2 aka 1
now the numerators just count up from 90°
cos(90) = 0 / 2
cos(60) = 1 / 2
cos(45) = [tex]\sqrt{2}[/tex] / 2
cos(30) = [tex]\sqrt{3}[/tex] / 2
cos(0) = [tex]\sqrt{4}[/tex] / 2 aka 1
see the pattern.. it's pretty easy to memorize, knowing that :)
now let's use the above to plug into the given equation
16* [tex]\sqrt{3}[/tex] / 2 - 20* [tex]\sqrt{3}[/tex] / 2- 8*[tex]\sqrt{4}[/tex] / 2
8* [tex]\sqrt{3}[/tex] - 10 [tex]\sqrt{3}[/tex] -8
-2*[tex]\sqrt{3}[/tex] - 8
this isn't quite the same answer as you got before.. I feel like it's right