∑ DANEMATHICS
FREE CAPS MATHS RESOURCES
Grade 9 · Exponents
The Laws of Exponents: Complete Exam Guide
MEMORANDUM
Name:
Class:
Date:
Mark
/ 24
Answer all questions. Show all your working — marks are awarded for method as well as the final answer. Teacher copy: accept any correct equivalent method.
- 1Simplify x4 · x3 (Law 1)(1)Add exponents → x7✓ (1)
- 2Simplify 3a2 · 4a5 (Law 1)(2)3 × 4 = 12, add exponents → 12a7✓✓ (2)
- 3Simplify m8 ÷ m3 (Law 2)(1)Subtract exponents → m5✓ (1)
- 4Simplify 20x6/5x2 (Law 2)(2)20 ÷ 5 = 4, subtract exponents → 4x4✓✓ (2)
- 5Simplify (a3)2 (Law 3)(1)Multiply exponents → a6✓ (1)
- 6Simplify (2y4)3 (Law 4)(2)23 = 8, and the exponents multiply: 4 × 3 = 12 → 8y12✓✓ (2)
- 7Simplify (3x2)2 (Law 4)(2)32 = 9 → 9x4✓✓ (2)
- 8Evaluate 7x0, where x ≠ 0 (Law 5)(1)x0 = 1 → 7✓ (1)
- 9Evaluate (5y)0, where y ≠ 0 (Law 5)(1)Whole bracket to power 0 → 1✓ (1)
- 10Write 4x−2 with a positive exponent (Law 6)(2)4/x2✓✓ (2)
- 11Simplify (2x3)2 · x (combined)(2)(2x3)2 = 4x6, ×x → 4x7✓✓ (2)
- 12Simplify 12a5b2/4a2b6 (combined)(3)12 ÷ 4 = 3, a5 − 2 = a3, b2 − 6 = b−4 → 3a3/b4✓✓✓ (3)
- 13Write 3 200 000 in scientific notation(2)3,2 × 106✓✓ (2)
- 14Write 0,0007 in scientific notation(2)Small number → negative power → 7 × 10−4✓✓ (2)
TOTAL: 24 marks