3 5 12 13 July 8, 2019 16 32 64 128 Cos 3 5 12 13 3 5 x 12 13 Sin 3 5 12 13 3 5 6 x 12 13 3 4 5 triangle 5 12 13 Sina 3 5 cosb 12 13 3 4 5 and 5 12 13 Sin 3 5 cos 12 13 Sinx 3 5 cosy =- 12 13 Sina 3 5 cosb 12 13 cos a b