# Can you multiply to infinity?

Calculus Level 3

Evaluate the given expression for Q:

$$\displaystyle\prod _{ n=2 }^{ \infty }{ (1-\frac { 1 }{ { n }^{ 2 } } ) }$$ = $$\textbf{Q}$$

If $$\textbf{Q}$$ can be represented as $$\frac { a }{ b }$$, where $$\textbf{a}$$ and $$\textbf{b}$$ are coprime integers, then what is $$a+b$$?

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