Respuesta :

lucic

Answer:

None of these

Step-by-step explanation:

The two cases are for trigonometry special angles.

The cosine of an angle is given as the adjacent side length divided by the hypotenuse side length

Cos ∅ = A/H

1. The case of 45°,45°,90°

Cos x = 1 /√2

2. The case of 30°, 60° ,90°

Cos x = 1/2   or  √3/2