Find the values of x such that
$$2 \log_x{(x-2)} = 2$$ - Edexcel - A-Level Maths Pure - Question 4 - 2012 - Paper 3

Question 4

Find the values of x such that
$$2 \log_x{(x-2)} = 2$$
Worked Solution & Example Answer:Find the values of x such that
$$2 \log_x{(x-2)} = 2$$ - Edexcel - A-Level Maths Pure - Question 4 - 2012 - Paper 3
Rearranging the Equation

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First, we can rewrite the equation as:
2logx(x−2)=2
To simplify, divide both sides by 2:
logx(x−2)=1
Using the Definition of Logarithms

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Using the definition of logarithms, we convert the log equation:
x1=x−2
This simplifies to:
x=x−2
Setting Up the Quadratic Equation

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We rearrange this to form:
x−x+2=0
This leads us to:
x2−9x+18=0
Factoring the Quadratic

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Next, we factor the quadratic:
(x−3)(x−6)=0
Finding the Solutions

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Setting each factor to zero gives us:
x−3=0orx−6=0
Therefore, the solutions are:
x=3andx=6
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