P+3 p-3 (p+3)(p-4) - (p-3)(p+4)
-------- - ------ = ---------------------------- =
p+4 p-4 P^2 - 16
p^2 -4p +3p -12 -p^2-4p+3p+12 ) -2p
------------------------------------------- = ----------
p^2-16 p^2 -16
7p+g p+7g 7p+g p+7g 7pg+g^2 -p^2-7gp
---------- + ------------- = ---------- - ------------- = ------------------------- =
p(p-g) g(g-p) p(p-g) g(p-g) pg(p-g)
g^2 -p^2 (p-g)(p+g) p +g
----------- = - ------------------ = - -----------
gp(p-g) gp (p-g) pg