a = [1 0 -1 0 1]; % (x^4 - x^2 + 1)
b = [-2 2 1 4]; % (-2x^3 + 2x^2 + x + 4)
c = [1 2 -2]; % (x^2 + 2x -2)
% multiplying a and b for left side
ab = conv(a,b);
% of (4 / c), move c to the left of the equal sigh
% so we have (a*b) / c = 4
abc = deconv(ab,c);
% now move 4 to the other side
D = [abc 4];
% now we have (a*b)/c - 4 = 0
% now we find the roots
r = roots(D)