Jika sinx=513\sin x=\frac{5}{13}sinx=135 maka cos2x=....\cos2x=....cos2x=....
50169\frac{50}{169}16950
119169\frac{119}{169}169119
140169\frac{140}{169}169140
144169\frac{144}{169}169144
25169\frac{25}{169}16925