1. **State the problem:** Find the value of $\cot 231^\circ 48'$ and simplify it to a decimal rounded to eight decimal places.
2. **Convert the angle to decimal degrees:**
$$231^\circ 48' = 231 + \frac{48}{60} = 231 + 0.8 = 231.8^\circ$$
3. **Use the cotangent identity:**
$$\cot \theta = \frac{1}{\tan \theta}$$
4. **Find the reference angle:**
Since $231.8^\circ$ is in the third quadrant (between $180^\circ$ and $270^\circ$), the reference angle is:
$$231.8^\circ - 180^\circ = 51.8^\circ$$
5. **Evaluate $\tan 231.8^\circ$ using the reference angle:**
In the third quadrant, tangent is positive, so:
$$\tan 231.8^\circ = \tan 51.8^\circ$$
6. **Calculate $\tan 51.8^\circ$ (approximate):**
$$\tan 51.8^\circ \approx 1.25864044$$
7. **Calculate $\cot 231.8^\circ$:**
$$\cot 231.8^\circ = \frac{1}{\tan 231.8^\circ} = \frac{1}{1.25864044} \approx 0.79404039$$
**Final answer:**
$$\cot 231^\circ 48' \approx 0.79404039$$
Cotangent Value B0B89A
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.