Given that `cosx/2.cosx/4.cosx/8....=sinx/x` Then find the sum `1/2^2sec^2x/2+1/2^4sec^2x/4+...`

Explanation

To solve the problem, we start with the given equation:

\[ \frac{\cos x}{2} \cdot \frac{\cos x}{4} \cdot \frac{\cos x}{8} \cdots = \frac{\sin x}{x} \]

### Step 1: Taking the logarithm of both sides

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