Exponential Rules
Maths: Edexcel A Level Pure Maths, topic 2.1.1
Laws of Powers (Indices)
These are the laws that tell us what to do with powers. Powers are sometimes called indices.
Multiplying powers
- Add the powers when multiplying powers of the same number.
Dividing powers
- Subtract the powers when dividing powers of the same number.
Power raised to another power
- If an expression with a power is raised to another power, multiply the powers.
Fractions
- Apply a power to both top and bottom of a fraction.
Negative powers
- A negative power means 1 over the positive power.
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 0
Test yourself on Exponential Rules
What is 71?
What is 21?
What is 20?
What is 360?
What is 23 × 26?