1. **Problem statement:** Given a stadium-shaped figure with rectangle length $AB = CD = 100$ m, width $BC = AD = 40$ m, and diagonal $AC = 118.7$ m, find $\sin(\angle ACD)$, $\cos(\angle ACD)$, and $\tan(\angle ACD)$.
2. **Identify the triangle and angle:** The angle $\angle ACD$ is at vertex $C$ formed by points $A$, $C$, and $D$. We consider triangle $ACD$.
3. **Use the Law of Cosines to find $\angle ACD$:** The sides of triangle $ACD$ are $AC = 118.7$ m, $CD = 100$ m, and $AD = 40$ m (width). The angle $\angle ACD$ is opposite side $AD$.
The Law of Cosines states:
$$\cos(\angle ACD) = \frac{AC^2 + CD^2 - AD^2}{2 \times AC \times CD}$$
4. **Calculate $\cos(\angle ACD)$:**
$$AC^2 = 118.7^2 = 14088.69$$
$$CD^2 = 100^2 = 10000$$
$$AD^2 = 40^2 = 1600$$
Substitute:
$$\cos(\angle ACD) = \frac{14088.69 + 10000 - 1600}{2 \times 118.7 \times 100} = \frac{22488.69}{23740} \approx 0.947$$
5. **Calculate $\angle ACD$ in radians or degrees:**
$$\angle ACD = \arccos(0.947) \approx 18.9^\circ$$
6. **Calculate $\sin(\angle ACD)$ and $\tan(\angle ACD)$:**
$$\sin(\angle ACD) = \sqrt{1 - \cos^2(\angle ACD)} = \sqrt{1 - 0.947^2} = \sqrt{1 - 0.896} = \sqrt{0.104} \approx 0.323$$
$$\tan(\angle ACD) = \frac{\sin(\angle ACD)}{\cos(\angle ACD)} = \frac{0.323}{0.947} \approx 0.341$$
**Final answers:**
$$\sin(\angle ACD) \approx 0.323$$
$$\cos(\angle ACD) \approx 0.947$$
$$\tan(\angle ACD) \approx 0.341$$
Angle Acd Trig 8D36C1
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.