Editing Talk:2509: Useful Geometry Formulas

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:: I expanded the text slightly, and worked out the correct formula: it should be (2π - 2arctan(h/a))ab + b sqrt(h^2 - a^2). Can someone verify that, format it properly for the wiki, and add it? The easy way to check it is to shrink the diagram horizontally so the ellipse is a circle of radius a. (Does the wiki not have MathJax or similar installed? Seems odd, given Randall Munroe's interests.) It's maybe also worth mentioning that looking closely at the picture at a pixel level shows that he did draw the tangents, rather than do the half-ellipse + triangle that the formula suggests. --[[Special:Contributions/172.69.90.75|172.69.90.75]] 16:48, 2 September 2021 (UTC)
 
:: I expanded the text slightly, and worked out the correct formula: it should be (2π - 2arctan(h/a))ab + b sqrt(h^2 - a^2). Can someone verify that, format it properly for the wiki, and add it? The easy way to check it is to shrink the diagram horizontally so the ellipse is a circle of radius a. (Does the wiki not have MathJax or similar installed? Seems odd, given Randall Munroe's interests.) It's maybe also worth mentioning that looking closely at the picture at a pixel level shows that he did draw the tangents, rather than do the half-ellipse + triangle that the formula suggests. --[[Special:Contributions/172.69.90.75|172.69.90.75]] 16:48, 2 September 2021 (UTC)
  
; It's 3am (okay 5am) and I made it really long!
+
== It's 3am (okay 5am) and I made it really long! ==
  
 
I just followed the directions in the "incomplete" which said to add in explanations of the formulae ... Please feel free to edit to take out redundancy.  However I did add in the following explanations:
 
I just followed the directions in the "incomplete" which said to add in explanations of the formulae ... Please feel free to edit to take out redundancy.  However I did add in the following explanations:

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