設(shè)n元二次型f(x1,x2,···,xn)的矩陣為n階五對(duì)角對(duì)稱(chēng)矩陣,試寫(xiě)出二次型的表達(dá)式.
寫(xiě)出下列實(shí)對(duì)稱(chēng)矩陣所對(duì)應(yīng)的二次型: