(a).
\The ellipse is
and the point is
.
Rewrite the function as
.
Apply derivative on each side with respect to
.


\



.
Slope of the tangent at point is the derivative of the function at that point.
\The derivative of the function at
.
Substitute
and
in
.
.
Slope of the tangent at point
is
.
The general form of the equation is
.
Substitute
and
in the function
.

Substitute
and
in the function
.
The tangent line equation is
.
(b).
\ The functionn is
and the point is 
Rewrite the function as
.
Apply derivative on each side with respect to
.


\


Slope of the tangent at point is the derivative of the function at that point.
\The derivative of the function at
.
Substitute
and
in
.
.
Slope of the tangent at point
is
.
The general form of the equation is
.
Substitute
and
in the function
.

.
Substitute
and
in the function
.




Substitute
in the function
then
.
Substitute
in the function
.
The tangent line equation is
.
(a) The tangent line equation is
.
(b) The tangent line equation is
.