If `y=(log)_(sinx)(tanx),t h e n(((dy)/(dx)))_(pi/4)"is equal to"` (a)`4/(log2)` (b) `-4log2` (c)`(-4)/(log2)` (d) none of these

Explanation

To solve the problem, we need to find the derivative of the function \( y = \log_{\sin x} (\tan x) \) and evaluate it at \( x = \frac{\pi}{4} \).

### Step 1: Rewrite the function using logarithmic properties
The function can be rewritten using the change of base formula for logarithms:
\[ y = \frac{\log(\tan x)}{\log(\sin x)} \]

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