Question

a ray from the positive x - axis is rotated - 270°. what is the cosine of the angle formed by this ray? (1 point)

Explanation:

Step1: Find the equivalent positive angle

Since \(-270^{\circ}+360^{\circ} = 90^{\circ}\), the angle \(-270^{\circ}\) is coterminal with \(90^{\circ}\).

Step2: Calculate the cosine value

We know that \(\cos\theta=\frac{x}{r}\). For \(\theta = 90^{\circ}\), in the unit - circle (\(r = 1\)), \(x=0\). So \(\cos(90^{\circ})=0\).

Answer:

\(0\)