function prolozeni
t=[1:5];
u=[15,18,19,21,24];
plot(t,u,'o')
k=polyfit(t,u,2);
disp(k)
xj=linspace(0.5,5.5,1000);
y=polyval(k,xj);
hold on
plot(xj,y,'r')
hold off
end

