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Softplus function ( $lo g (1 + e^{x})$ )

The softplus function

s (x) = lo g (1 + e^{x})

is convex because

s^{''} (x) = \frac{e ^{x}}{( 1 + e ^{x} ) ^{2}} > 0.

 Ancestors (6)

 Incoming links (1)

Solution