Given that angle $dcu$ is in standard position and its terminal side passes through the point $(0,1)$ on the unit circle, what is the measure of angle $dcu$ in degrees?

• A. $0°$
• B. $90°$
• C. $270°$
• D. $180°$

Answer: (B)

Verified step by step guidance

1. Recognize that the point (0, 1) lies on the unit circle, which means its coordinates satisfy the equation \(x^2 + y^2 = 1\).
2. Recall that an angle in standard position has its vertex at the origin and its initial side along the positive x-axis, with the terminal side passing through the given point.
3. Identify the coordinates (0, 1) correspond to the point on the unit circle where the x-coordinate is 0 and the y-coordinate is 1, which is directly above the origin on the y-axis.
4. Understand that the angle whose terminal side passes through (0, 1) is the angle that points straight up from the positive x-axis, which corresponds to \(90^\circ\).
5. Conclude that the measure of angle \(dcu\) in degrees is \(90^\circ\) because this is the angle formed by the terminal side passing through (0, 1) on the unit circle.