The function is
and
.
Find the value
.
Case(i): 
(Original function)
(Substitute
)
(Simplify)
(Multiply each side by
)
Case(ii):
.
(Original function)
(Substitute
)
(Simplify)
(Multiply)
(Multiply each side by
)
Add both cases.
\
.
.
Therefore, the value of
is
.
.