The discretized signal y (xn) = yn; (n = 0; N-1) are given by the values in the table: x = 0; 0.2; 0.4; 0.6; 0.8; one; 1.2; 1.4; 1.6; 1.8; y = -0.8; -0.6; 0.2; 0.7; 0.9; 1.4; 0.8; 0.4; 0.1; -0.2;
It is necessary to smooth the data (approximation) using the polynomial Pi (x) = a0 + a1x;
Actually the problem is solved. But in the solution the logic of the solution is invisible ... 
There is a Minimize function (s, a0, a1), it needs to be replaced with the "open" full solution. With this and need your help.
ps in theory, there should be a system of equations and it needs to be solved.