Implicit Scheme
We obtain now
ui,j−1=−αui−1,j+(1−2α)ui,j−αui+1,j.
Here
ui,j−1 is the only unknown quantity.
Defining the matrix
A
A=[1+2α−α00…−α1+2α−α0…………………………−α00…−α1+2α],
we can reformulate again the problem as a matrix-vector multiplication
AVj=Vj−1