#calculus

mkwadee@diasp.eu

My wife was working through finding the derivative of the #exponential #function #exp(x) from first principles. I was made aware that she hadn't actually seen why the number e=2.7128... was the #base the of the function and that that's what you need to start with. In fact, that means one must actually start by finding the first differential of a general #logarithm and find #e from there. Once you've find the #FirstDerivative of #ln(x), the #derivative of the #ExponentialFunction is straightforward.

Anyway, here it for anyone who might be interested for education purposes.
Page 1 of deriving the differential of the log function
Page 2 of deriving the differential of the log function
Page 3 of deriving the differential of the log function

#Calculus #Derivative #Mathematics #Differentiation #CCBYSA

mkwadee@diasp.eu

A couple of weeks ago, I posted an #animation of a point on a circle generating a #cycloid.
Generating a cycloid

If you turn the curve "upside down", you get the #BrachistochroneCurve. This curve provides the shortest travel time starting from one cusp to any other point on the curve for a ball rolling under uniform #gravity. It is always faster than the straight-line travel time. This is an interesting problem in #ClassicalMechanics and exercised luminaries like #Newton and #Euler. I think the latter's use of the #CalculusOfVariations is a stroke of genius.

Anyway, the #animation took a bit of thought as it requires a bit of #Mechanics, some #Integration and is made a bit more tricky as the curve is multi-valued and so you need to treat different branches separately. The #AnimatedGif was produce with #WxMaxima.

For some reason that I can't fathom, I'm not finding it possible to upload the graphic and so if you want to see it, please use the link below.
https://drive.google.com/file/d/1edcZnZ_uiaQOQrFB03XHslNUVCmxcSut/view?usp=drive_link

#MyWork #CCBYSA #Mathematics #Maths #AppliedMathematics #Physics #Calculus