MATLAB: Function with two inputs and arguments

Question

Hello I am stuck on a problem. I am supposed to make a function that solves quadratic equations. If however the function gives complex numbers, it is supposed to give me the anwsers x1=888, x2=888. How do I do this?

if then

I tried;

function [xp,xm] = find_roots(a,b,c)
if b^2-4*a*c<0
    xp=888 & xm=888
else
    xp=(-b/(2*a))+sqrt(b^2-4*a*c)/(2*a)
    xm=(-b/(2*a))-sqrt(b^2-4*a*c)/(2*a)
end      % end function

However it if far from the right anwser. I basically don't know how to do arguments in a function. I even tried the "==" in the if/else statement in my function and it still did not work.

Can anyone help me?

Thanks in advance!

Answer 1

The & is misused. Try:

function [xp,xm] = find_roots(a,b,c)
if b^2-4*a*c<0
    xp=888;
    xm=888;
else
    xp=(-b/(2*a))+sqrt(b^2-4*a*c)/(2*a);
    xm=(-b/(2*a))-sqrt(b^2-4*a*c)/(2*a);
end 

Also have a look at the built-in roots

doc roots