There are several typographical errors, at lelast with respect to the code representing the symbolic equations in the image.
With those corrections, ‘Numerical’ and ‘Exact’ are the same (within floating-point approximation error), at least for the values provided.
k = reshape(0:100, 1, 1, );
B = (t.^(k.*alpha)).*(r-4).^k ./ (factorial(k).*alpha.^k);
Exact = exp(x+((r-4).*(t.^alpha)./(alpha)));
Error = Numerical - Exact;
ErrorRMS = sqrt(mean(Error.^2))
legend([hZ1(1),hZ2(1)], 'CFRDTM','EXACT', 'Location','NE')
It would also help if the code was parsed into different lines (as I had to do here), in order for it to run.