`cos^(-1)((3cosx-2sinx)/(sqrt(13)))`

Explanation

To solve the problem \( y = \cos^{-1}\left(\frac{3\cos x - 2\sin x}{\sqrt{13}}\right) \), we need to find \( \frac{dy}{dx} \).

### Step-by-Step Solution:

1. **Identify the function**:
\[ y = \cos^{-1}\left(\frac{3\cos x - 2\sin x}{\sqrt{13}}\right) \]
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