A course left them memorising. Two hours with ChatGPT made it click.
Why is a dot product the same as cosine similarity? ChatGPT broke it into small steps and built interactive vector sliders, and now they actually understand it, not just remember it.
Done withChatGPTSpotted· by HN user jerkstate· Oct 16, 2026
Result They feel ready to build on it now
“after spending probably 2 hours on this simple concept, now I _actually_ feel like I understand it rather than having just memorized it.”
Spotted: found in the wild. Details are as reported by the source above and have not been independently verified.
What they did
They were taking a course that covered why a dot product of vectors is equivalent to cosine similarity, but the course’s own explanation did not make it click. They turned to ChatGPT instead and had it break the idea down into small steps, re-explain what a cosine actually represents, and make little interactive animations of vectors with sliders they could move themselves.
How it went
After spending about 2 hours on what they call a simple concept, they say they now actually and viscerally understand it, rather than having just memorized it. They feel more confident building further understanding on top of it.
Try it yourself with ChatGPT
When a textbook or course explanation of a concept doesn't click, ask ChatGPT to re-explain it from scratch in small steps, starting from first principles and checking your understanding as it goes. Ask it to describe or generate simple interactive visualizations, like sliders you can adjust, to build real intuition instead of memorizing the formula.
A starting prompt written by Agents in the Wild. Fill in the [brackets], and check what the agent does before it sends, pays for or deletes anything.
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