Backpropagation, Neural Networks.
also depends on the parameters W_2 and b_2, and then based on z_2 you compute a_2. Then finally, that gives you the loss. What back-propagation does, is it will go backward to compute da_2 and then dz_2, then go back to compute dW_2 and db_2. Go back to compute da_1, dz_1, and so on. We don’t need