CGLQuantitative AptitudeAlgebra BasicsCurated by Prabhakar Bhatt, Founder of क्रांति · Last reviewed 2 July 2026# Algebra Basics - (a+b)² = a² + 2ab + b² - (a-b)² = a² − 2ab + b² - a² − b² = (a-b)(a+b) If x + 1/x = k, then x² + 1/x² = k² − 2.