NUMBERS

• integers : whole numbers (eg 0, 1, -5)
• rational : can be expressed as a fraction
• irrational : CANNOT be expressed as a fraction

PRIME FACTORISATION

eg :

2 | 220

2 | 110

5 | 55

11| 11

1

∴ 220 = 2² x 5 x 11

HCF :

• highest common factor of 2> numbers

eg :

HCF of 18 and 30

= 2 x 3

= 6

LCM :

• lowest common multiple of 2> numbers

eg :

LCM of 5, 15 and 30

= 2 x 3 x 5 (common prime factors)

= 30

LAWS OF INDICES

• aᵐ x aⁿ = aᵐ⁺ⁿ
• aᵐ ÷ aⁿ = aᵐ⁻ⁿ
• (aᵐ)ⁿ = aᵐⁿ
• aⁿ x bⁿ= (ab)ⁿ
• aⁿ ÷ bⁿ = (a/b)ⁿ
• a⁰ = 1
• a⁻ⁿ = 1/aⁿ
• 1/aⁿ = ⁿ√a
• aᵐ/ⁿ= ⁿ√aᵐ