Power Rules & Collecting Terms

Maths: Edexcel IGCSE Higher, topic 2.1.2

Laws of Powers (Indices)

These are the laws that tell us what to do with powers. Powers are sometimes called indices.

Multiplying powers

Multiplying powers

  • Add the powers when multiplying powers of the same number.
Dividing powers

Dividing powers

  • Subtract the powers when dividing powers of the same number.
Power raised to another power

Power raised to another power

  • If an expression with a power is raised to another power, multiply the powers.
Fractions

Fractions

  • Apply a power to both top and bottom of a fraction.
Negative powers

Negative powers

  • A negative power means 1 over the positive power.
Roots

Roots

  • x1/2 means the square root of x.
  • x1/3 means the cube root of x.
  • All roots can be written as x1/n = n√x.
Power of 1

Power of 1

Power of 0

Power of 0

Collecting Terms

Simplify the following expression by collecting terms:

Simplify

Simplify

x terms

x terms

xy terms

xy terms

Numbers

Numbers

Test yourself on Power Rules & Collecting Terms

  • What is 71?

  • What is 21?

  • What is 20?

  • What is 360?

  • What is 23 × 26?

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