Take a complicated fraction with the product of five quartics top
and bottom and reduce this to a whole number. This is a numerical
example involving some clever algebra.
This article only skims the surface of Galois theory and should
probably be accessible to a 17 or 18 year old school student with a
strong interest in mathematics.
Step back and reflect! This article reviews techniques such as
substitution and change of coordinates which enable us to exploit
underlying structures to crack problems.