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What are the domain and range of the logarithmic function f(x) = log7x? Use the inverse function to justify your answers.

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What are the domain and range of the logarithmic function f(x) = log7x? Use the inverse-example-1
User Llm
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Answer with explanation:

The given logarithmic function whose base is, 7 is


y=f(x)=\log_(7)x

Domain of a function is defined as, set of all possible values of , x , for which ,y is defined.


\log_(7)x=(\log x)/(\log 7)

is defined for,

→ log x > 0.

⇒ x ∈ (0,∞)

And range of a function is defined as those values of y, for which x, is defined.


y=\log_(7)x\\\\y=(\log x)/(\log 7)\\\\ \log x =y \log 7\\\\x=7^y

So, Range = y∈ (0,∞).

The inverse of the above function can be obtained by, replacing, x by y, and y by x , in the above equation:

So, the inverse of the above function is :


y=7^x

Here, x ∈ (0,∞) and, y ∈ (0,∞).

User Tymbark
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