1. **State the problem:** Simplify and verify the equation $\tan^2 x \sin^2 x = \tan^2 x - \sin^2 x$.
2. **Recall definitions and identities:**
- $\tan x = \frac{\sin x}{\cos x}$
- $\tan^2 x = \frac{\sin^2 x}{\cos^2 x}$
3. **Rewrite the left side using $\tan^2 x$:**
$$\tan^2 x \sin^2 x = \frac{\sin^2 x}{\cos^2 x} \sin^2 x = \frac{\sin^4 x}{\cos^2 x}$$
4. **Rewrite the right side:**
$$\tan^2 x - \sin^2 x = \frac{\sin^2 x}{\cos^2 x} - \sin^2 x = \frac{\sin^2 x}{\cos^2 x} - \frac{\sin^2 x \cos^2 x}{\cos^2 x}$$
5. **Combine the right side over common denominator:**
$$= \frac{\sin^2 x - \sin^2 x \cos^2 x}{\cos^2 x} = \frac{\sin^2 x (1 - \cos^2 x)}{\cos^2 x}$$
6. **Use Pythagorean identity $1 - \cos^2 x = \sin^2 x$:**
$$= \frac{\sin^2 x \sin^2 x}{\cos^2 x} = \frac{\sin^4 x}{\cos^2 x}$$
7. **Compare both sides:**
Left side = $\frac{\sin^4 x}{\cos^2 x}$, right side = $\frac{\sin^4 x}{\cos^2 x}$, so the equation holds true.
**Final answer:** The equation $\tan^2 x \sin^2 x = \tan^2 x - \sin^2 x$ is an identity and is true for all $x$ where $\cos x \neq 0$.
Tan Sin Identity 904928
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