1. **State the problem:** We want to prove by induction that the infinite nested radical expression $$x = \sqrt{2 + \sqrt{2 + \sqrt{2 + \cdots}}}$$ satisfies $$x < 2$$.
2. **Define the sequence:** Let $$a_1 = \sqrt{2}$$ and $$a_{n+1} = \sqrt{2 + a_n}$$ for $$n \geq 1$$. We want to show $$a_n < 2$$ for all $$n$$, and then conclude about the limit.
3. **Base case:** For $$n=1$$, $$a_1 = \sqrt{2} \approx 1.414 < 2$$. So the base case holds.
4. **Inductive hypothesis:** Assume $$a_k < 2$$ for some $$k \geq 1$$.
5. **Inductive step:** Show $$a_{k+1} < 2$$.
We have
$$
a_{k+1} = \sqrt{2 + a_k}.
$$
Using the inductive hypothesis $$a_k < 2$$,
$$
a_{k+1} < \sqrt{2 + 2} = \sqrt{4} = 2.
$$
6. **Conclusion:** By induction, $$a_n < 2$$ for all $$n$$.
7. **Limit:** Since $$a_n$$ is increasing and bounded above by 2, the limit $$x = \lim_{n \to \infty} a_n$$ exists and satisfies
$$
x = \sqrt{2 + x}.
$$
Squaring both sides,
$$
x^2 = 2 + x.
$$
Rearranged,
$$
x^2 - x - 2 = 0.
$$
Solving the quadratic,
$$
x = \frac{1 \pm \sqrt{1 + 8}}{2} = \frac{1 \pm 3}{2}.
$$
Since $$x > 0$$, we take
$$
x = 2.
$$
Thus, the infinite nested radical converges to 2, but each finite approximation $$a_n < 2$$.
**Final answer:** The nested radical expression is always less than 2 for any finite number of radicals, and converges to 2 in the limit.
Nested Radical 4B51C5
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