How to keep my complex root answers un-simplified?

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I've created a formula to calculate complex roots in editor and have the following:
a=input('Enter the value for a: ');
b=input('Enter the value for b: ');
c=input('Enter the value for c: ');
if b^2 > 4*a*c
root_1=(-b+sqrt(b^2-4*a*c))/2*a;
root_2=(-b-sqrt(b^2-4*a*c))/2*a;
fprintf('\n')
disp('Roots are real and distinct:')
fprintf(1,'Root1= %0.0f \n',root_1);
fprintf(1,'Root2= %0.0f \n',root_2);
elseif b^2 == 4*a*c
root_1=-b/(2*a);
root_2=-b/(2*a);
fprintf('\n')
disp('Roots are repeated:')
fprintf(1,'Root1=Root2= %0.0f \n',root_1);
elseif b^2 < 4*a*c
root_1=(-b/2*a)+(sqrt(4*a*c-b^2)/2*a);
root_2=(-b/2*a)-(sqrt(4*a*c-b^2)/2*a);
fprintf('\n')
disp('Roots are complex:')
fprintf(1,'Root1= %0.0f \n',root_1);
fprintf(1,'Root2= %0.0f \n',root_2);
end
So far everything works fine but I don't want the last "elseif" command to simplify the imaginary equation.
For instance if my (a,b,c) are (1,8,25), respectfully, the answer that I would like to have is:
Root1= -4+3i
Root2= -4-3i
How do I keep it this way or at least have the "i"?

Accepted Answer

Walter Roberson
Walter Roberson on 28 Jun 2012
fprintf(1,'Root1= %0.0f%+0.0fi\n', real(root_1), imag(root_1));
  9 Comments
Tom
Tom on 28 Jun 2012
It might be worth checking it with a known solution (e.g. http://www.mathgoodies.com/calculators/quadratic_equations.html)- try for example a=3,b=4,c=1
Aaron
Aaron on 28 Jun 2012
Edited: Aaron on 28 Jun 2012
Sonovagun!! I should have caught that. Thank you.

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