The original expression simplifies to

To simplify the given expression
, we can break it down step by step. Let

1. Substitute \(y\) into the innermost square root:
![\[ \sqrt{4 + \sqrt{4 + √(4 + x^2)}} = \sqrt{4 + √(4 + y)} \]](https://img.qammunity.org/2024/formulas/mathematics/college/k9yqks0su3ssvexmzy7t51spegj36hfup3.png)
2. Substitute \(y\) into the next layer:
![\[ \sqrt{4 + √(4 + y)} = √(4 + y) \]](https://img.qammunity.org/2024/formulas/mathematics/college/xmvn6fw0zw8x1gg6fhlpsvs66gxm86b9zv.png)
3. Substitute \(y\) one last time:
![\[ √(4 + y) = \sqrt{4 + √(4 + x^2)} \]](https://img.qammunity.org/2024/formulas/mathematics/college/bj1a30sj5fcw1ya0t2yynlb85ckggtzr1v.png)
So, the simplified expression is

Now, substitute y back in to get the final expression in terms of x:
![\[ \sqrt{4 + √(4 + x^2)} = \sqrt{4 + \sqrt{4 + √(4 + x^2)}} \]](https://img.qammunity.org/2024/formulas/mathematics/college/kt2a78qaddgt7634nbauzdc9rpfehfje46.png)