Identifying special situations in factoring

• Difference of two squares
  • a²- b² = (a + b)(a - b)
  • (x + 3)(x − 3)
  • (5x − 1)(5x + 1)
  • (x³ − 3)(x³ + 3)
• Trinomial perfect squares
• a² + 2ab + b² = (a + b)(a + b) or (a + b)²
• x² + 2x + 1 = 0
• x² + 4x + 2 = 0
• ^{a2 - 2ab + b2 = (a - b)(a - b) or (a - b)2}
• • 3 examples
• Difference of two cubes
  • a³ - b³
    • 3 - cube root 'em
    • 2 - square 'em
    • 1 - multiply and change
      • 3 examples
• Sum of two cubes
  • a³ + b³ 
    • 3 - cube root 'em
    • 2 - square 'em
    • 1 - multiply and change
      • 3 examples
• Binomial expansion
  • (a + b)³ = Use the pattern
  • (a + b)⁴ = Use the pattern