• Codex@lemmy.world
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      1 month ago

      The semi-circle is one side, then the 2 straight edges, and the arc between them is the 4th side.

    • UrLogicFails@beehaw.org
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      1 month ago

      Someone may want to double-check my math on this one, but the length of the sides will be dependant on the radius of the smaller circle

      ϴ=π+1-√(π^2+1), l=(2π-ϴ)r_1, l is the length of the sides. r_1 is the radius of the smaller circle

      • m0darn@lemmy.ca
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        1 month ago

        I look at your diagram and see:

        ϴ= L/(L+R)
        

        And

        2π-ϴ = L/R
        

        I solved those and got

        L= π-1 ± √(1+π²) ~= 5.44 or -1.16
        

        Whether or not a negative length is meaningful in this context is an exercise left to the reader

        Giving (for L=5.44):

        ϴ~= 0.845 ~~48.4° 
        

        I’m surprised that it solved to a single number, maybe I made a mistake.

        • UrLogicFails@beehaw.org
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          1 month ago

          That lines up pretty similarly with what I found also. The angle should be a constant since there is only one angle where the relationship would be true. I just left it in terms of π because I try to avoid rounding.

          Having said that, L would be a ratio of r; which I think lines up with what you found as well.