Jawabanmu

2014-03-19T17:08:44+07:00
Y = cos 60 = 1/2 y= cos 45 = 1/2 akar 2 y = 3. cos 30 = 3/2 akar 3 y = 3. cos 45 = 3/2 akar 2
2014-03-19T17:15:35+07:00
1. cos 2X 30 = cos 60 = 1/2
2. cos 2 X 45 = cos 90 = 0
3. 3 X cos 30 = 2X akar3/2 = akar 3
4. 3 X cos 45 = 3X akar 2/2 = 3 akar 2/2
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