The function is
and point is
.
.
Apply derivative on each side with respect to
.
.
Product rule of derivatives :
.

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