AP Calculus: Related Rates Problem - Square Inscribed in Circle

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[jumbopopcorn]

Makes calculus video
Needs to explain the area of a circle

45-45-90 and 30-60-90 I still haven't memorized

found a simpleefied: 3:42

4:11 your 2's kind of look like 1's, slightly confusing

6:20 -- I think you could have spent a little more time talking about the general rule (like the area formulas) because it is a calculus video after all (also funnily enough I found this rule myself by playing around in desmos for a while)

Syntax Question: You write dr/dt, but I thought that the "r" means "in respect to function r"? But r is this case is not a function, but a value. Or maybe it means you are defining r by making the derivative. (Could that also be written as r'(t) = -1/2t)?

8:36 I have a question here -- if you're generalizing the rate of change for the area, then how can you plug in the radius directly? Wouldn't it then be related to just that point?

Oh, I got it. Correct me if I'm wrong, but the shaded region's area would be a curve, while the radius a line. Taking the derivative of r yields the same slope -- a constant rate of change. But the area is non-linear, meaning you are finding the slope of the tangent line at that point, right?

Great video!