1. **State the problem:**
Solve and verify the trigonometric identity:
$$\frac{1}{\cot^2 x} + \frac{1}{\sin x \cos x} = \sec^2 x$$
2. **Recall formulas and identities:**
- $\cot x = \frac{\cos x}{\sin x}$
- $\sec x = \frac{1}{\cos x}$
- $\cot^2 x = \frac{\cos^2 x}{\sin^2 x}$
- Pythagorean identity: $\sin^2 x + \cos^2 x = 1$
3. **Rewrite the left side using $\cot^2 x$:**
$$\frac{1}{\cot^2 x} = \frac{1}{\frac{\cos^2 x}{\sin^2 x}} = \frac{\sin^2 x}{\cos^2 x}$$
4. **Rewrite the second term:**
$$\frac{1}{\sin x \cos x}$$
5. **Sum the two terms on the left:**
$$\frac{\sin^2 x}{\cos^2 x} + \frac{1}{\sin x \cos x}$$
6. **Find common denominator $\cos^2 x \sin x$:**
$$\frac{\sin^2 x \sin x}{\cos^2 x \sin x} + \frac{\cos^2 x}{\cos^2 x \sin x} = \frac{\sin^3 x + \cos^2 x}{\cos^2 x \sin x}$$
7. **Simplify numerator if possible:**
No direct simplification, so keep as is.
8. **Check if this equals $\sec^2 x = \frac{1}{\cos^2 x}$:**
Multiply both sides by $\cos^2 x \sin x$:
$$\sin^3 x + \cos^2 x = \frac{\cos^2 x \sin x}{\cos^2 x} = \sin x$$
9. **Rewrite equation:**
$$\sin^3 x + \cos^2 x = \sin x$$
10. **Rearrange:**
$$\sin^3 x - \sin x + \cos^2 x = 0$$
11. **Use $\cos^2 x = 1 - \sin^2 x$:**
$$\sin^3 x - \sin x + 1 - \sin^2 x = 0$$
12. **Group terms:**
$$\sin^3 x - \sin^2 x - \sin x + 1 = 0$$
13. **Factor by grouping:**
$$\sin^2 x (\sin x - 1) - (\sin x - 1) = (\sin x - 1)(\sin^2 x - 1) = 0$$
14. **Factor $\sin^2 x - 1$ as difference of squares:**
$$(\sin x - 1)(\sin x - 1)(\sin x + 1) = 0$$
15. **Solutions:**
$$\sin x = 1 \quad \text{or} \quad \sin x = -1$$
16. **Check domain restrictions:**
$\cot x$ and $\sin x \cos x$ must be defined (nonzero denominators).
17. **Final conclusion:**
The identity holds true for values of $x$ where $\sin x = \pm 1$ and denominators are defined.
**Answer:** The equation is true for $x$ such that $\sin x = 1$ or $\sin x = -1$ with domain restrictions respected.
Trig Identity F70C67
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