Robuta

https://www.wolframalpha.com/input/?i=plot+(1-%7Cr%7C)%5E3+r%3D-1..1 plot (1-|r|)^3 r=-1..1 - Wolfram|Alpha 1 r 3plotwolframalpha https://www.wolframalpha.com/input?i=%281%2Fr+%281-1%2Fr%29%29%5E%28-3%2F2%29 (1/r (1-1/r))^(-3/2) - Wolfram|Alpha 1 r 32wolframalpha