Extremal curvature of graph y = exp(x)

Task 1
Point with extremal curvature is NOT the vertex of the curve.
Determine the extremal curvature k of the graph y=exp(x)
Task 2
Vertex of parabola [i](y + x)[sup]2[/sup] = x[br][/i]Parametrization of parabola: [i]X = [t[sup]2[/sup]; t-t[sup]2[/sup]][br][/i]Maximal curvature 5.66
– Šárka Voráčová

Information: Extremal curvature of graph y = exp(x)