I'm not sure. I'm trying to get it right.
T(n) = T(n-1)+T(n/2)+n
As we know we Asymptotic notation by equalities and inequalities, we can represent a part of Sub expression in RHS with a Approx Fn.
lets consider T(n/2)+n. By applying masters theorem we get => O(n).
So Our initial Eqn becomes, T(n)= T(n-1)+O(n). Now if we apply masters theorem we get T(n)= O(n^2).
Please Correct me if im wrong