function [ out,N1,N2,D ] = f( theta )

    L1 = 2;
    L2 = sqrt(2);
    L3 = sqrt(2);
    gamma = pi/2;
    p1 = sqrt(5);
    p2 = sqrt(5);
    p3 = sqrt(5);
    x1=4;
    x2=0;
    y1=0;
    y2=4;

    A2=L3*cos(theta)-x1;
    B2=L3*sin(theta);
    A3=L2*cos(theta+gamma)-x2;
    B3=L2*sin(theta+gamma)-y2;
    N1=B3*(p2^2-p1^2-A2^2-B2^2)-B2*(p3^2-p1^2-A3^2-B3^2);
    N2=-A3*(p2^2-p1^2-A2^2-B2^2)+A2*(p3^2-p1^2-A3^2-B3^2);
    D=2*(A2*B3-B2*A3);
    out=N1^2+N2^2-p1^2*D^2;
    
    
end