b
------------------------
/ a -a - b\
(a - b)*|----- + ------|
\a - b a / b
-----------------------
/ a a + b\
(a - b)*|----- - -----|
\a - b a /b/((a - b)*(a/(a - b) - (a + b)/a))
a*b -------------------- 2 a - (a + b)*(a - b)
b
-----------------------
/ a a + b\
(a - b)*|----- - -----|
\a - b a /