艾滋病病毒检测的确证试验通常采用何种方法
A、竞争法B
暂无解析
设f(x,y)具有一阶偏导数,且对任意的(x,y),
设随机变量(X,Y)服从二维正态分布N(0,0;1,4;-1/2),随机变量中服从标准正态分布且与X独立的是()
行列式
Inordertolivethekindoflifewewantandtobethepersonwewanttobe,wehavetodomorethanjust________withevents.
heteachertoldthemsincelight________(travel)fasterthansound,lightning________(appear)togobeforethunder.