(a)
\The equation of tractrix is
.
Differentiate on each side with respect to
.

Derivative of the hyperbolic secant function:
.


.
(b)
\The equation of tractrix is
,
.
From (a):
\
.
Slope of the tangent is derivative of the function at the given point.
\Let the point
is
.
.
Slope of the tangent line is
.
Point-slope form of line equation is
.
Substitute
and
in the above equation.
The tangent line is
.
The tangent line intersects the
-axis at point
.
Substitute
in
.


.
The distance between
and
is
.

Substitute
.



.
The distance between
and
is
.
(a)
.
(b) The distance between
and
is
.