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3:05 PM
$$\frac{dy}{dx}=\lim_{\Delta x\to 0}\frac{\Delta y}{\Delta x}$$
 
 
2 hours later…
4:46 PM
@Shinrin-Yoku Sorry that I did not respond to your comment - busy with some stuff IRL.
I left a few brief messages in Calculus chatroom.
But is seem that you've figured it yourself anyway.
 

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