Respuesta :

Answer:

Step-by-step explanation:

Sin A ÷ 2 = 2

Sin A = 2×2

Sin A = 4

Cos A = sqrt (1 - Sin ^2 A) = sqrt(1 - 4^2)

Cos A = sqrt(1-16) = sqrt (-15) = sqrt(15i^2)

Cos A = i sqrt(15)