X Coordinate
1. The problem asks for the x-coordinate of point A, which lies on a circle centered at the origin with radius 1.
2. Point A is in the second quadrant, and the angle between the positive x-axis and the line segment from the origin to A is $\frac{\pi}{5}$ radians.
3. The formula for the coordinates of a point on a circle of radius $r$ at an angle $\theta$ from the positive x-axis is:
$$x = r \cos(\theta), \quad y = r \sin(\theta)$$
4. Since the radius $r = 1$, the x-coordinate of point A is:
$$x = \cos\left(\frac{\pi}{5}\right)$$
5. However, point A is in the second quadrant where x-values are negative, so:
$$x = -\cos\left(\frac{\pi}{5}\right)$$
6. Evaluating $\cos\left(\frac{\pi}{5}\right)$ numerically:
$$\cos\left(\frac{\pi}{5}\right) \approx 0.8090$$
7. Therefore, the x-coordinate of point A is approximately:
$$x \approx -0.8090$$
Final answer: The x-coordinate of point A is $-\cos\left(\frac{\pi}{5}\right) \approx -0.8090$.