Identifying special situations in factoring

• Difference of two squares
• a²- b² = (a + b)(a - b)
• a²- 4 = (a + 2)(a - 2)
• a²- 64 = (a + 8)(a - 8)
• a²- 9 = (a + 3)(a - 3)
• Trinomial perfect squares
• a² + 2ab + b²= (a + b)(a + b) or (a + b)²
• a² + 2a + 4= (a + 2)(a + 2) or (a +2)²
• a² + 8a + 16= (a + 4)(a + 4) or (a + 4)²
• a² + 6+9= (a + 3)(a + 3) or (a + 3)² 
• Difference of two cubes
• a³ - b³
• 3 - cube root 'em
• 2 - square 'em
• 1 - multiply and change
• a³ - 2 = (a - 2)(a² + a + 2)
• a³ - 64 = (a - 3)(a² + 4a + 16)
• Sum of two cubes
• a³ + b³ 
• 3 - cube root 'em
• 2 - square 'em
• 1 - multiply and change
• q³+1 = (q+1)(q²+q+1)
• a³+100 = (a+10)(a²-10a+5)
• Binomial Expansion
• (a + b)³ = (x+y)³ = x³ + 6x²y + 6xy² + y³
• (a + b)⁴ = (x+y)⁴ = x⁴ + 8x³y + 10x²y² + 8xy³ + y⁴