Mathematician Finds Easier Way to Solve Quadratic Equations

[Albert Chan]

KISS quad solver

Code:

function quad(a,b,c)
    b = -.5*b
    local y = I.sqrt(b*b-a*c)
    y = I.abs(b+y) < I.abs(b-y) and b-y or b+y
    return y/a, c/y
end

lua> quad(1e-13,-2,1)
(19999999999999.496+0*I)      (0.5000000000000125+0*I)