All the Backpropagation derivatives

This is easy to solve as we already computed'dz' and the second term is simply the derivative of'z' which is'wX b' w.r.t'b' which is simply 1! For completeness we will also show how to calculate'db' directly. To calculate this we will take a step from the above calculation for'dw', (from just before we did the differentiation) Taking the LHS first, the derivative of'wX' w.r.t'b' is zero as it doesn't contain b! The derivative of'b' is simply 1, so we are just left with the'y' outside the parenthesis.