Jawabanmu

2014-03-30T16:25:07+07:00
1.sin (-330) = -sin 330 = -sin (360-30) = -sin (-30) = 1/2
tan 210 = tan (180+30) = tan 30 = 1/3 \sqrt{3}
cos 300 = cos (360-60) = -cos 60 =  -1/2 (di kuadran 4) = 1/2
sin 225 = sin (180+45) = sin 45 = 1/2 \sqrt{2}
jadi 1/2-1/2 \sqrt{3} - 1/2.1/2 = 3-2 \sqrt{3} /6 - 1/4 = 3-4 \sqrt{3} /12

2. \pi = 180
sin 7/6.180 = sin 210 = sin (180+30) = sin 30 = 1/2
tan 4/3.180 = tan 240 = tan (180+60) = tan 60 =  \sqrt{3}
cos -1/3.180 = -cos 60 = - 1/2
jadi 1/2. \sqrt{3} .-2 = - \sqrt{3}

maaf kalau salah ya..