Error in W1A3 Gradient Check

In the final excersize in this assignment, when I run the gradient check, my output is always “There is a mistake in the backward propagation! difference = 0.2591160168052715,” which is the incorrect value for the difference. The notebook says I am supposed to be outputting “difference = 0.2850931567761623.” I have looked over my code for hours and I have no idea what bug is causing this small error. Does anyone else know how to fix this? Thanks!

Fixed by @tshah1.

Pay attention to the formula:


The subscript _2 means 2-norm.

Good luck with the rest of the course :slight_smile: