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Iflog, b=c, is it possible for c to equal a negativenumber? Explain your answer.

Iflog, b=c, is it possible for c to equal a negativenumber? Explain your answer.-example-1
User Skym
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1 Answer

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\log _a(b)=c

Using the definition of the base of a log:


\log _a(b)=c\equiv a^c=b

According to this, c could be a negative number, here's why:

Let's try to find the following logarithm:


\log _2((1)/(8))=c

Using the definition of the base of a log:


2^c=(1)/(8)

We can express 8 as 2³:


2^c=(1)/(2^3)

Using the following property:


a^(-x)=(1)/(a^x)

We can express the equation as:


2^c=2^(-3)

From this, we can conclude that c = -3, therefore it is possible for x to equal a negative number.

User Olavi Mustanoja
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