Asked about Derivatives and the chain rule

Why do gradients vanish in deep networks?

An answer that works

The chain rule multiplies derivatives along the path, so many factors below one shrink towards zero and early layers receive almost no signal. Residual connections and activations like ReLU exist largely to counter this.

Reading an answer is not being able to give one. The section that teaches this is Derivatives and the chain rule, 5 hours of Calculus for ML.

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