Step 1:
\The function is
and point is
.
Change-of-base formula for logarithm property :
.

Apply derivative on each side with respect to
.

.
Step 2:
\Find slope at the point
.
Substitute
in derivative of the function.

.
Slope of a tangent line is
.
Point - slope form of a line equation is
.
Substitute
and
in point - slope form.

The tangent line equation is
.
Step 3:
\Graph :
\Graph the function
and tangent line is
:

Solution :
\The tangent line equation is
.