The speed of a ball is
.
The height is
.
The angle is
.
The value of
.
(a)
\Time as a parameter in parametric equations are
and
.
Substitue the values in
.


.
The parametic equation is
instead of
to see the vertical motion better.
Substitute the values in
.


.
Therefore, the parametric equations of the ball as a function of time are
and
.
(b)
\Find the length of the ball in the air.
\The ball is in the air untill
.
Equate
to
.




or
.
or
.
The time is always postive.
\Therefore, the ball is in the air for
seconds.
(c)
\Find the time when the ball is in the maximum height.
\The maximum height occurs at the vertex of the quadratic function.
\The maximum height is at
.
The quadratic equation is
.
The general form of quadratic equation is
.
Compare the equation with general form.
\Here
,
and
.
Substitute
,
in
.


.
The maximum height occurs at
seconds.
substitute
in
.

.
Therefore, the maximum height is
.
(d)
\Graph:
\Graph the function
.

(a) The parametric equations of the ball as a function of time are
and
.
(b) The ball is in the air for
seconds.
(c) The maximum height is
is occurs at
.
(d)
\