Which of the following correctly uses the special triangles on the unit circle to determine θ in degrees when cosθ=2√2 ? You may assume that 0°≤θ≤180° . (1 point) Responses 90° 90 degrees 45° 45 degrees 30° 30 degrees 60°
cosine of θ = adjacent/hypotenuse
Since cosθ = 2√2, let's identify the adjacent side and the hypotenuse using the special triangles on the unit circle.
From the 45-45-90 triangle, we know that the ratio of the adjacent side to the hypotenuse is √2/2.
Therefore, in this case, the adjacent side is 2√2 and the hypotenuse is 2.
So, the ratio of the adjacent side to the hypotenuse in this case is √2/2.
By comparing the ratios, we can determine that θ = 45°.
Therefore, the correct answer is 45°.