(a + b)² = a² + 2ab + b²

(a – b)² = a² – 2ab + b²

(a – b)(a + b) = a² – b²

(a + b)³ = a³ + 3a²b + 3ab² + b³

(a – b)³ = a³ – 3a²b + 3ab² – b³

a³ + b³ = (a + b)(a² – ab + b²)

a³ – b³ = (a – b)(a² + ab + b²)

a4+b4=(a2+b2 + ab√2)(a2+b2 − ab√2)

a * 3√5 = 3√5a3

(a – 1)(a + 1) = a² – 1

(x² – 2) = (x – √2)(x + √2)