Edexcel A Level Maths: Pure:复习笔记6.2.1 Laws of Logarithms

What are the laws of logarithms?

• There are many laws or rules of indices, for example
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• There are equivalent laws of logarithms (for a > 0)
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• There are also some particular results these lead to
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• Two of these were seen in the notes Logarithmic Functions
• Beware …
  • … log (x + y) ≠ log x + log y
• Results apply to ln too
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  • In particular

How do I use the laws of logarithms?

• Laws of logarithms can be used to …
  • … simplify expressions
  • … solve logarithmic equations
  • … solve exponential equations