(a)
\The triangle side is
and angle is 
The laws of sines : 
The angle
is acute angle,
Recall the relation from the ambiguous case:
.
If triangle has one solution and
is an acute angle , then
and
.
and
.
Substitute
,
in
.


If triangle has one solution, then values of
are
and
.
(b)
\If triangle has two solutions and
is an acute angle , then
.
Substitute the corresponding value in above formula.
\
.
Divide each side by
.



Finally conclude that
.
(c)
\If triangle has no solution and
is an acute angle, then
.

Divide each side by
.

Substitute
and
in above expression.
.
(a)
and
.
(b)
.
(c)
.