Two unified formulae

The trace identity, the quadratic-form identity and the tri-trace identity, which all contain the constant γ, are all simple and powerful tools for producing Hamiltonian structure. The first formula obtained in the Letter is a unified expression of the above three formulas. Its role is to open an approach for setting up similar formulas in other mathematical or physical applications. The second formula given in the Letter is a unified computational one on the constant γ which appears in the above three formulae. This succeeds in overcoming the problem on the computing the constant γ, proposed by Tu Guizhang and left open for long time.