% ex = poly_2_ex (l, f) - Extremum of a 1-var deg-2 polynomial % % l : 3 : Values of variable at which polynomial is known. % f : 3 : f(i) = Value of the degree-2 polynomial at l(i). % % ex : 1 : Value for which f reaches its extremum % % Assuming that f(i) = a*l(i)^2 + b*l(i) + c = P(l(i)) for some a, b, c, % ex is the extremum of the polynome P. %