# I don't know the difference between dZL = AL - Y and dZL = dAL .\* g'(ZL)

**URL:** <https://community.deeplearning.ai/t/i-dont-know-the-difference-between-dzl-al-y-and-dzl-dal-g-zl/96740>\
**Category:** Neural Networks and Deep Learning\
**Tags:** coursera-platform\
**Created:** [February 8, 2022, 2:18pm UTC](https://community.deeplearning.ai/t/i-dont-know-the-difference-between-dzl-al-y-and-dzl-dal-g-zl/96740 "2022-02-08T14:18:13Z")\
**Posts on this page:** 1\
**Showing post:** 5

<div class="post-metadata">

**Author:** ![paulinpaloalto](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/paulinpaloalto/32/187_2.png) [@paulinpaloalto](https://community.deeplearning.ai/u/paulinpaloalto)\
**Post date:** [March 3, 2026, 3:49pm UTC](https://community.deeplearning.ai/t/i-dont-know-the-difference-between-dzl-al-y-and-dzl-dal-g-zl/96740/5 "2026-03-03T15:49:30Z")

</div>

That is beyond the scope of these courses, but there are lots of other webpages that cover the calculus behind all this. [Here’s a thread](https://community.deeplearning.ai/t/course-1-week-3-backpropagation-intuition/7979/2) with pointers to get you started on that. I got that link from one of the topics on the [DLS FAQ thread](https://community.deeplearning.ai/t/faq-frequently-asked-questions-for-all-dls-courses/74), which is worth a look just on general principles if you haven’t already seen it.

---

_[View the full topic](https://community.deeplearning.ai/t/i-dont-know-the-difference-between-dzl-al-y-and-dzl-dal-g-zl/96740)._