IGCSE Maths Notes: Solving Logarithmic Equations
A summary of log equations will be useful
(1)
(2)
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(3)
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(4)
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(5)
If
then![]()
(6)
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In the examples that follow I will indicate where each rule has been used.
Example: Solve![]()
Apply (1) to give
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Apply (6) to give
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x cannot be -4 because
does
not exist, so![]()
Example: Solve
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(5) gives
Substitute
to give
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Multiply by p to give
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We have to find x using
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and
Using
(6).
Example: Solve![]()
(2) gives
Use
(6) to give
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