First hidden layer for \(k=1,...,K_{1}\)
\[A_{k}^{(1)}=h_k^{1}(X)\]
Second hidden layer for \(l=1,...,K_2\)
\[A_{k}^{(2)}=h_k^{2}(X)\]
Figure 10.5: Multilayer Neural Network - Chap 10
