Question

Which of the following is the inverse of y=3^x

Please hurry

A. y= 1/3^x

B. y=log3x

C. y=(1/3)^x

D. y=log1/3x

Answer 1

y=3^x is an exponential function. We want the inverse function, which is a log function.

Here the base is 3. Taking log to the base 3 of y=3^x,

(log to the base 3 of y) = x (answer)

Answer 2

`y=log_3x`

Explanation:

We want to find the inverse of
`y=3^x`.

We interchange
`x` and
`y` to obtain,

`x=3^y`.

We now make y the subject by taking logarithm of both sides to base 3 to get,

`log_3x=log_33^y`.

`log_3x=y\:log_33`.

`\Rightarrow log_3x=y\:(1)`.

`\Rightarrow y=log_3x`

The correct answer is B.