1. **State the problem:**
We need to verify or simplify the equation $$\frac{1 + \tan y}{1 + \cot y} = \frac{\sec y}{\csc y}$$.
2. **Recall the definitions:**
- $$\tan y = \frac{\sin y}{\cos y}$$
- $$\cot y = \frac{\cos y}{\sin y}$$
- $$\sec y = \frac{1}{\cos y}$$
- $$\csc y = \frac{1}{\sin y}$$
3. **Rewrite the left side using definitions:**
$$\frac{1 + \tan y}{1 + \cot y} = \frac{1 + \frac{\sin y}{\cos y}}{1 + \frac{\cos y}{\sin y}}$$
4. **Find common denominators inside numerator and denominator:**
Numerator:
$$1 + \frac{\sin y}{\cos y} = \frac{\cos y}{\cos y} + \frac{\sin y}{\cos y} = \frac{\cos y + \sin y}{\cos y}$$
Denominator:
$$1 + \frac{\cos y}{\sin y} = \frac{\sin y}{\sin y} + \frac{\cos y}{\sin y} = \frac{\sin y + \cos y}{\sin y}$$
5. **Rewrite the entire fraction:**
$$\frac{\frac{\cos y + \sin y}{\cos y}}{\frac{\sin y + \cos y}{\sin y}}$$
6. **Divide by a fraction by multiplying by its reciprocal:**
$$= \frac{\cos y + \sin y}{\cos y} \times \frac{\sin y}{\sin y + \cos y}$$
7. **Cancel common factors:**
Since $$\cos y + \sin y = \sin y + \cos y$$, they cancel:
$$= \cancel{\frac{\cos y + \sin y}{\cos y}} \times \cancel{\frac{\sin y}{\sin y + \cos y}} = \frac{\sin y}{\cos y}$$
8. **Simplify the left side:**
$$\frac{1 + \tan y}{1 + \cot y} = \frac{\sin y}{\cos y} = \tan y$$
9. **Simplify the right side:**
$$\frac{\sec y}{\csc y} = \frac{\frac{1}{\cos y}}{\frac{1}{\sin y}} = \frac{1}{\cos y} \times \frac{\sin y}{1} = \frac{\sin y}{\cos y} = \tan y$$
10. **Conclusion:**
Both sides simplify to $$\tan y$$, so the equation is true.
**Final answer:**
$$\frac{1 + \tan y}{1 + \cot y} = \frac{\sec y}{\csc y} = \tan y$$
Trig Identity Cca5E5
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