1. **State the problem:** Prove or verify the identity $$\sec^6\theta + \tan^6\theta = 1 + 3 \tan^2\theta \sec^2\theta$$.
2. **Recall the fundamental identity:** We know that $$\sec^2\theta = 1 + \tan^2\theta$$.
3. **Express everything in terms of $$\tan\theta$$:**
Since $$\sec^2\theta = 1 + \tan^2\theta$$, then $$\sec^6\theta = (\sec^2\theta)^3 = (1 + \tan^2\theta)^3$$.
4. **Rewrite the left side:**
$$\sec^6\theta + \tan^6\theta = (1 + \tan^2\theta)^3 + \tan^6\theta$$.
5. **Expand $$(1 + \tan^2\theta)^3$$ using the binomial theorem:**
$$ (1 + x)^3 = 1 + 3x + 3x^2 + x^3 $$ where $$x = \tan^2\theta$$.
So,
$$ (1 + \tan^2\theta)^3 = 1 + 3 \tan^2\theta + 3 \tan^4\theta + \tan^6\theta $$.
6. **Substitute back:**
$$\sec^6\theta + \tan^6\theta = 1 + 3 \tan^2\theta + 3 \tan^4\theta + \tan^6\theta + \tan^6\theta = 1 + 3 \tan^2\theta + 3 \tan^4\theta + 2 \tan^6\theta$$.
7. **Rewrite the right side:**
$$1 + 3 \tan^2\theta \sec^2\theta = 1 + 3 \tan^2\theta (1 + \tan^2\theta) = 1 + 3 \tan^2\theta + 3 \tan^4\theta$$.
8. **Compare both sides:**
Left side: $$1 + 3 \tan^2\theta + 3 \tan^4\theta + 2 \tan^6\theta$$
Right side: $$1 + 3 \tan^2\theta + 3 \tan^4\theta$$
They are not equal unless $$2 \tan^6\theta = 0$$, which is only true if $$\tan\theta = 0$$.
**Conclusion:** The given identity $$\sec^6\theta + \tan^6\theta = 1 + 3 \tan^2\theta \sec^2\theta$$ is **not true** for all $$\theta$$.
**Final answer:** The identity does not hold in general.
Sec Tan Identity Bf00Ba
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