Jawabanmu

2014-03-15T08:29:47+07:00
Tan A = y/x = -1/2 r^2 = y^2 + x^2 r^2 = -1^2 + 2^2 r^2 = 1 + 4 r^2 = 5 r = akar 5 sin A = y/r = -1/akar5 cos A = x/r = 2/akar5 jadi nilai sin A x cos A = -1/akar 5 x 2/akar 5 = -2/5 (tolong jadikan solusi terbaik atau jawaban terbaik please)
2014-03-15T08:45:26+07:00