REVISION NOTES

IGCSE Edexcel Further Pure Mathematics

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1.1 Logarithmic Functions and Indices

1.1.1 The functions ax and logb x (where b is a natural number greater than one)

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1.1.2 Use properties of indices and logarithms, including change of base

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For example log232 = 5 means that 25 = 32

In words, you would say ‘the logarithm of 32, to base 2, is 5

To remove log, solve for x:

  1. On one side: use concept of log to remove
    1. E.g. log2x = 4 → x = 24 = 16
  2. On two sides: use change of base law (rule 8 above), to make both logarithms have the same base, then cancel out log
  3. When solving log in quadratic: make “logab = x” to solve as a normal quadratic, then replace values of “x” to equal “logab”

Natural log

loge = ln

Always keep final answer always in ln

1.1.3 Simple manipulation of surds

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1.1.4 Rationalising the denominator

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