1. **Simplify** $\frac{1 + \sec(-\theta)}{\sin(-\theta) + \tan(-\theta)}$.
Recall the even-odd properties of trig functions:
- $\sec(-\theta) = \sec \theta$ (secant is even)
- $\sin(-\theta) = -\sin \theta$ (sine is odd)
- $\tan(-\theta) = -\tan \theta$ (tangent is odd)
Substitute these:
$$\frac{1 + \sec \theta}{-\sin \theta - \tan \theta} = \frac{1 + \sec \theta}{-(\sin \theta + \tan \theta)} = - \frac{1 + \sec \theta}{\sin \theta + \tan \theta}$$
Rewrite $\tan \theta = \frac{\sin \theta}{\cos \theta}$ and $\sec \theta = \frac{1}{\cos \theta}$:
$$- \frac{1 + \frac{1}{\cos \theta}}{\sin \theta + \frac{\sin \theta}{\cos \theta}} = - \frac{\frac{\cos \theta + 1}{\cos \theta}}{\sin \theta \left(1 + \frac{1}{\cos \theta}\right)}$$
Simplify denominator:
$$\sin \theta \left(\frac{\cos \theta + 1}{\cos \theta}\right)$$
So expression is:
$$- \frac{\frac{\cos \theta + 1}{\cos \theta}}{\sin \theta \frac{\cos \theta + 1}{\cos \theta}}$$
Cancel $\frac{\cos \theta + 1}{\cos \theta}$ top and bottom:
$$- \frac{\cancel{\frac{\cos \theta + 1}{\cos \theta}}}{\sin \theta \cancel{\frac{\cos \theta + 1}{\cos \theta}}} = - \frac{1}{\sin \theta} = - \csc \theta$$
**Answer:** $- \csc \theta$ (option 5).
---
2. **Simplify** $\cot^2 y (\sec^2 y - 1)$.
Recall identity:
$$\sec^2 y - 1 = \tan^2 y$$
So expression becomes:
$$\cot^2 y \cdot \tan^2 y$$
Recall $\cot y = \frac{1}{\tan y}$, so:
$$\cot^2 y \tan^2 y = \left(\frac{1}{\tan y}\right)^2 \tan^2 y = 1$$
**Answer:** $1$ (option 3).
---
3. **Find** $\ln |\sec \theta|$.
Recall $\sec \theta = \frac{1}{\cos \theta}$, so:
$$\ln |\sec \theta| = \ln \left| \frac{1}{\cos \theta} \right| = - \ln |\cos \theta|$$
**Answer:** $- \ln |\cos \theta|$ (option 3).
---
4. **Simplify** $\cos^2 \beta - \sin^2 \beta$.
Recall identity:
$$\cos 2\beta = \cos^2 \beta - \sin^2 \beta$$
Also recall:
$$\cos 2\beta = 2 \cos^2 \beta - 1$$
So:
$$\cos^2 \beta - \sin^2 \beta = 2 \cos^2 \beta - 1$$
**Answer:** $2 \cos^2 \beta - 1$ (option 1).
Trig Simplifications B745Ae
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.