W4 A1- not using the provided functions

Course Q&A Deep Learning Specialization Neural Networks and Deep Learning
1

Hi All,

In the W4 A1, Exercise 8: we are provided with a relu_backward(dA,activation_cache) function to compute dZ.

Do we have to use the provided function or can I implement it from
dZ = dA * g’(Z)

e.g. for Relu: dZ = dA * ( Z > 0)

2

Yes, you have to use it. Simply call it where it is required. No need to do that math stuff.