This exam tips covers Common Mistakes to Avoid within Index Laws for GCSE Mathematics. Revise Index Laws in Number for GCSE Mathematics with 14 exam-style questions and 22 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 12 of 14 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Common Mistakes to Avoid
❌ Wrong: 2³ × 3² = 6⁵
✅ Right: Cannot combine - different bases
Index laws only work with same base
❌ Wrong: (2³)⁴ = 2⁷
✅ Right: (2³)⁴ = 2¹²
Multiply powers, don't add
❌ Wrong: 5⁰ = 0
✅ Right: 5⁰ = 1
Any number to power 0 equals 1 (except 0⁰)
❌ Wrong: 2⁻³ = -8
✅ Right: 2⁻³ = 1/8
Negative power ≠ negative number
Practice questions for Index Laws
Which of these is equivalent to a³ × a⁵?
Simplify a⁵ × a³
Quick recall flashcards
Zero Power Law
a⁰ = 1
ANY number to power 0 equals 1
(except 0⁰ which is undefined)
Examples: 5⁰ = 1, 100⁰ = 1
Division Law
aᵐ ÷ aⁿ = aᵐ⁻ⁿ
SUBTRACT the powers
Example: 5⁶ ÷ 5² = 5⁴