The function is  and point is .

Change of base formula for logarithm property : .

Apply derivative on each side with respect to .

.

Find slope at the point

Slope of the tangent line is derivative of the function at given point..

Substitute  in .

.

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 .

Graph :

Graph the function  and tangent line is :

The tangent line equation is .