Differentiate `(log)_7((log)_7x)` with respect to `x` :

Explanation

To differentiate the function \((\log_7(\log_7 x))\) with respect to \(x\), we will follow these steps:

1. **Substitute and Simplify:**
Let \(u = \log_7 x\). Then the given function becomes \(y = \log_7 u\).

2. **Differentiate \(y\) with respect to \(u\):**
We know that the derivative of \(\log_a u\) with respect to \(u\) is \(\frac{1}{u \ln a}\). Here, \(a = 7\), so:
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