Diketahui 15 Cot A = 8, tentukan sin A dan sec A

cot A = cos A/sin A = 8/15
r² = 8² + 15²
r² = 64 + 225
r² = 289
r = √289
r = 17

sin A = 15/17

sec A = 1/cos A
         = 1/(8/17)
         = 17/8