$\"\"$

The exponential function is $\"\"$ .

Apply the initial conditions to find the $\"\"$ value.

Observe the graph :

At the point $\"\"$ :

When $\"\"$ , $\"\"$ .

Thus, $\"\"$ .

The exponential function is $\"\"$ .

Above graph passes through the point $\"\"$ .

Substitute $\"\"$ in the function $\"\"$ .

$\"\"$

Logarithmic definition : $\"\"$ .

$\"\"$

Substitute $\"\"$ in $\"\"$ .

$\"\"$

$\"\"$ .