Plus and minus sign for an equation

I need the plus and minus sign before the square root function, am I doing it right?

a=((xx+yy)/2)+sqrt((((xx+yy)^2)/2)+xy^2);

a=[a,-a];

Answer 1

[Walter Roberson]

No.

t1=((xx+yy)/2);
t2=sqrt((((xx+yy)^2)/2)+xy^2);
a=[t1+t2, t1-t2];

[Rooy]

Thank you for the help

Answer 2

[Naresh Virothi]

how to type plus or minus symbol in matlab

[John D'Errico]

Please don't add an answer just to ask a question.

And there is no plus OR minus symbol in MATLAB, that is, a symbol that indicates EITHER plus or minus.

Unless of course you just mean a string.

'+/-'
ans =
    '+/-'

[Walter Roberson]

>> char(177)
ans =
    '±'

However, this has no significance to equations and will be rejected as an error in source code except in comments or character vectors or string objects.

If you need this for labels, then, for example,

text(0.5,0.5,'$\pm$','interpreter','latex')

If you need the minus on top and the plus underneath then \mp