2 2m(m+1)
=
m^2 - 4 m(m-2)(m+2)(m+1)
3 3m(m-2)
m^2 + 3m + 2 m(m-2)(m+2)(m+1)
1 (m-2)(m+1)
m^2 + 2m m(m-2)(m+2)(m+1)
2 2m(m+1)
=
m^2 - 4 m(m-2)(m+2)(m+1)
3 3m(m-2)
=
m^2 + 3m + 2 m(m-2)(m+2)(m+1)
1 (m-2)(m+1)
=
m^2 + 2m m(m-2)(m+2)(m+1)