On the Unsolvable Quintic Equation x^5 + x^2 + x + 1/π = 0

Abstract

According to Galois’ theory, a solution x for the quintic equation cannot be solved for in radicals. Here we do not solve for x. We construct it. We note that radical numbers a and b can be found, such that a line that connects the points (a; f(a)) and (b; f(b)) passes through the interior point (x; 0), a root of the quintic function f(x). We then test this on f(x) = x5 +x2 + x+1/π. The values found for a and b, converted to decimal form, are a = −0.6012227544458956 and b = −0.6012348965947528, from which it is determined that x = −0.6012235335340363. The corresponding value, obtained through the software Mathematica numerical routines, is xn = −0.6012235335340362