3 t ( 2 ) t ( 1 ) 2 − 3 t ( 1 ) 2 + 3 t ( 2 ) 2 t ( 1 ) − 7 t ( 2 ) t ( 1 ) + 3 t ( 1 ) − 3 t ( 2 ) 2 + 3 t ( 2 ) t ( 1 ) t ( 2 ) {\displaystyle {\frac {3t(2)t(1)^{2}-3t(1)^{2}+3t(2)^{2}t(1)-7t(2)t(1)+3t(1)-3t(2)^{2}+3t(2)}{t(1)t(2)}}}
