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O level A-Math: Fatal Mistake In Logarithm Equation You Must Aviod
2 Comments · Posted by alwaysLovely in A-Math, Weekly Question
This is a common mistake I notice in my O level A-Math essential concepts revision workshop.
Solve the following equation:
First, you must identify the type of question since different types of question require different strategies.
It’s a different log-log question.
Strategy required: Change base.
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Change base formula used.
Reason for changing to base 2: Between changing to base 2 or x, we choose base 2 as x is an unknown, we choose not to work with THE unknown most of the time, don’t we?
Since we observe that there is a common term (log2 x),
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Did you observe the fatal mistake (It’s #7 Common mistake in Logarithm?
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The correct way to do the substitution would be:
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Solve the quadratic equation for y. Substitute the value back to find x.
Remember to check for validity of answers.
Related Posts:
- How To Solve “Clones” Type Of Logarithm Equations
- Logarithm Equation Question 2 [Checking validity of answers in logarithms equations]
- Linear Law,Just 1 Strategy Makes A Grade Difference
- Revisit: A-Math Logarithms Equations (Plus: Types of Equations & How To Identify Them Easily)
- Logarithm Equation Question 1
A-Math · logarithm equations · logarithms
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singaporeolevelmaths | Day 1 of ‘O’ level A-Math Essential Concepts Revision Workshop [Photos] · December 19, 2008 at 11:11 am
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[...] I’ll be sharing in the next few posts some of the fatal mistakes (Quadratic Equations, Logarithms) you must NEVER make! Let’s get the house rules right on day 1 before we begin learning. [...]