If the normals at \( \alpha, \beta, \gamma \), and \( \delta \) on an ellipse are concurrent, th... VIDEO
If the normals at \( \alpha, \beta, \gamma \), and \( \delta \) on an ellipse are concurrent, then the value of \( (\Sigma \cos \alpha)(\Sigma \sec \alpha) \) is
(a) 2
(b) 4
(c) 6
(d) 8
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