f(x) = 0.5·x^2
m[0 ; 2] = (f(2) - f(0))/(2 - 0) = 1
m[-1 ; 3] = (f(3) - f(-1))/(3 - (-1)) = 1
m[-1 ; 1] = (f(1) - f(-1))/(1 - (-1)) = 0
m[-2 ; -1] = (f(-1) - f(-2))/(-1 - (-2)) = -1.5
g(x) = 3·x^3 + 1
m[0 ; 2] = (g(2) - g(0))/(2 - 0) = 12
m[-1 ; 3] = (g(3) - g(-1))/(3 - (-1)) = 21
m[-1 ; 1] = (g(1) - g(-1))/(1 - (-1)) = 3
m[-2 ; -1] = (g(-1) - g(-2))/(-1 - (-2)) = 21