Discovery of explicit solution formulas for Polynomial eq. a₀xʲ+a₁xʲ⁻¹+…+aⱼ=0 j=2 Pythagoras (500 BC) j=3 Girolamo Cardano (1545) j=4 Lodovico Ferrari (1540) j≥5 No general formula exists, Niels Abel (1824)
At the age of 19, Gauss was the first person to accomplish the ruler and compass construction of a 17-gon polygon. This proof represented the first progress in regular polygon construction in over 2000 years. While doing it, he also discovered this expression for cos(2π/17) pic.twitter.com/AByfnuMDcr
