Let f : R → be a function given by \(f(x) = \left\lbrace \begin{matrix} \frac{1-\cos 2x}{x^2} & , & x < 0 \\\ α & , & x = 0 \\\ \frac{β \sqrt{1-\cos x}}{x} & , & x>0 \end{matrix} \right.\), where α, β ∈ R. If f is continuous at x = 0, then α2 + β2 is equal to:
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