I've been reading Penrose's Road to Reality where he presents two formulas for area of shperical triangles. the first is Lamberts which is(adsbygoogle = window.adsbygoogle || []).push({});

pi-(A+B+C)=area (where A,B,C are angles of triangle)

the other is Harriot's which is

Area=R^2(A+B+C-Pi)

What I'm trying to figure out is if the radius must be the same for each segment for these formulas to work. In other words, if you extrapolated each curved side of the triangle into a complete circle, do they all have to be the same size circles? I'm guessing they do, and increasing R would just change the scaling. But Lambert's formula does not require a radius so would that formula work for a triangle created from cirlces of different radius?

Hope I worded this in an understandable way.

dennis

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# Hyperbolic geometry question

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