We all know the easy way to solve the quadratic equation,           a x²+bx+c =0. W e use the quadratic formula for roots. We also have access to similar formulae for roots of cubic equations and quartic equations. The formula for roots of a cubic equation  ax 3 +bx 2 +cx+d=0 is  A similar complex looking formulae exist for roots of a quartic equation. But myster i ously we do not have any such formula for roots of 5 or higher degree polynomials. It seems as if, we can not construct the solutions of a degree 5 or higher degree polynomials just by using addition, subtraction, multiplication, division, and radicals in its coefficients.  Why so? what is so special in this 5-degree polynomial? These were questions that haunted the young Frenchman  Evariste Galois  in the 18th century. He developed a new mathematical object called a  “group”  that solved this issue in a surprisingly cool way. Galois being shot in a duel.  Image from...