Unit Circle Trig
1. **State the problem:**
We are given a point on the unit circle with coordinates
$$\left(-\frac{\sqrt{3}}{2}, \frac{1}{2}\right)$$
and asked to find:
i) The six trigonometric function values.
ii) The quadrant where this point lies.
iii) The angle made by this point with the positive x-axis.
2. **Calculate all six trigonometric functions:**
- Sine is the y-coordinate:
$$\sin \theta = \frac{1}{2}$$
- Cosine is the x-coordinate:
$$\cos \theta = -\frac{\sqrt{3}}{2}$$
- Tangent is sine divided by cosine:
$$\tan \theta = \frac{\sin \theta}{\cos \theta} = \frac{\frac{1}{2}}{-\frac{\sqrt{3}}{2}} = -\frac{1}{\sqrt{3}} = -\frac{\sqrt{3}}{3}$$
- Cotangent is the reciprocal of tangent:
$$\cot \theta = \frac{1}{\tan \theta} = -\sqrt{3}$$
- Secant is the reciprocal of cosine:
$$\sec \theta = \frac{1}{\cos \theta} = \frac{1}{-\frac{\sqrt{3}}{2}} = -\frac{2}{\sqrt{3}} = -\frac{2\sqrt{3}}{3}$$
- Cosecant is the reciprocal of sine:
$$\csc \theta = \frac{1}{\sin \theta} = \frac{1}{\frac{1}{2}} = 2$$
3. **Determine the quadrant:**
- The x-coordinate is negative and the y-coordinate is positive.
- Therefore, the point lies in the **second quadrant**, where x < 0 and y > 0.
4. **Calculate the angle formed:**
- Recognize the reference angle where sine is \( \frac{1}{2} \) and cosine is \( \frac{\sqrt{3}}{2} \), which is \(30^\circ\) or \(\frac{\pi}{6}\).
- Since the point is in the second quadrant, the angle with the positive x-axis is:
$$\theta = 180^\circ - 30^\circ = 150^\circ$$
or in radians:
$$\theta = \pi - \frac{\pi}{6} = \frac{5\pi}{6}$$
**Final summary:**
- $$\sin \theta = \frac{1}{2}, \quad \cos \theta = -\frac{\sqrt{3}}{2}, \quad \tan \theta = -\frac{\sqrt{3}}{3}$$
- $$\cot \theta = -\sqrt{3}, \quad \sec \theta = -\frac{2\sqrt{3}}{3}, \quad \csc \theta = 2$$
- Quadrant: Second
- Angle: $$\theta = \frac{5\pi}{6}$$ radians or $$150^\circ$$