function [b] = quadformel(a)
% Reality Check 4
% Aktivitet 1 og 2
c=299792.458;
A=[15600 18760 17610 19170];
B=[7540 2750 14630 610];
C=[20140 18610 13480 18390];
t=[0.07074 0.07220 0.07690 0.07242];
d2=a(1,1)^2+a(2,1)^2+a(3,1)^2-c^2;
d=2*a(1,1)*(a(1,2)-A(1))+2*(a(2,1)*(a(2,2)-B(1))+2*a(3,1)*(a(3,2)-C(1))+2*c^2*t(1);
k=(a(1,2)-A(1))^2+(a(2,2)-B(1))^2+(a(3,2)-C(1))^2-c^2*t(1)^2;
b=[d2;d;k];