Find the value of the infinite product ∏k=1∞cos(θ2k)\prod_{k=1}^\infty \cos(\frac{\theta}{2^k})∏k=1∞cos(2kθ).
sinθθ\frac{\sin\theta}{\theta}θsinθ
sinθθ\frac{\sin\theta}{\theta}θsinθ is wrong, answer is sinθθ\frac{\sin\theta}{\theta}θsinθ is also wrong, it is sinθθ\frac{\sin \theta}{\theta}θsinθ (Wait, it is sinθθ\frac{\sin \theta}{\theta}θsinθ
cos(θ)\cos(\theta)cos(θ)
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