The vector is
where
.
The vectors are
,
and
.
(a)
\Graph:
\Graph the vectors
and
,
and
.
.gif\")
(b)
\Draw the vector
starting at
and compare it with the vector
.
The vector is
.
Substitute
.
.
Substitute
.
.
Substitute
and
in
.


.
The vector is
.
the derivative of the function is
.
The vector is at the point
.

Compare the vector
with
.
Therefore, the derivative of the vector gives us the actual tangent vector at
.
(a)
\Graph:
\Graph the vectors
and
,
and
.
.gif\")
(b)
\The derivative of the vector gives us the actual tangent vector at
.