Scilab5_2

X = [-8 -2 3 11];
Y = [2 7 9 4];
plot2d(X, Y, -1, leg="Точки");

Y5 = [];
n = 3;

C = [];
C(1) = Y(1);
for i = 1:n
    s = Y(i+1) - C(1);
    for j = 1:i-1
        p = 1;
        for k = 0:j-1
            p = p * (X(i+1) - X(k+1));
        end
        s = s - p;
    end

    for j = 0:i-1
        s = s / (X(i+1) - X(j+1));
    end
    C(i+1) = s;
end

for x = -15:15
    s = C(1);
    for i = 1:n
        p = C(i+1);
        for j = 0:i-1
            p = p * (x - X(j+1));
        end
        s = s + p;
    end

    Y5 = [Y5, s];
end

plot2d(-15:15, Y5, style=[color("magenta")], leg="Метод Ньютона");