在 MATLAB 中求解二次方程

syms x
quad_equation1 = x^2 + 7*x + 10 == 0;
quad_equation2 = 7*x^2 + 5*x + 10 == 0;

X = solve(quad_equation1, x);
Y = solve(quad_equation2, x);

disp('The first root of the first quadratic equation is: '), disp(X(1));
disp('The second root of the first quadratic equation is: '), disp(X(2));

disp('The first root of the second quadratic equation is: '), disp(Y(1));
disp('The second root of the second quadratic equation is: '), disp(Y(2));

The first root of the first quadratic equation is:
-5

The second root of the first quadratic equation is:
-2

The first root of the second quadratic equation is:
- (255^(1/2)*1i)/14 - 5/14

The second root of the second quadratic equation is:
(255^(1/2)*1i)/14 - 5/14

function [x1, x2] = QuadraticEquation(a, b, c)

    % quad. formula
    d = b^2 - 4*a*c;
    % the real numbered distinct roots
    if d > 0
        x1 = (-b+sqrt(d))/(2*a);
        x2 = (-b-sqrt(d))/(2*a);
    % the real numbered degenerate root
    elseif d == 0
        x1 = -b/(2*a);
        x2 = NaN;
    % complex roots will return NaN, NaN.
    else
        x1 = NaN;
        x2 = NaN;
    end
end

[x1, x2] = QuadraticEquation (3, 4, -13)

[y1, y2] = QuadraticEquation (1,2,1)

[z1, z2] = QuadraticEquation (3, 3, 1)

x1 =

    1.5191


x2 =

   -2.8525


y1 =

    -1


y2 =

   NaN


z1 =

   NaN


z2 =

   NaN