MEPX
Chapter 6 of 10All chapters
  1. 1Why letters
  2. 2Rearranging
  3. 3Expanding and factorising
  4. 4Straight lines
  5. 5Quadratics
  6. 6Fractions and powers
  7. 7Two unknowns
  8. 8Inequalities
  9. 9Functions
  10. 10Turning words into algebra

Chapter 6 of 10

Fractions and powers

The rules that trip people up.

Powers

Multiplying powers of the same base adds the exponents; dividing subtracts them. A negative exponent means one over, and a fractional exponent means a root.

  • Anything to the power zero is 1.
  • x squared times x cubed is x to the fifth, not x to the sixth.

Algebraic fractions

Adding them needs a common denominator, exactly as with numbers. Cancelling is only allowed on factors, never on individual terms of a sum.