X线平均波长(λmean)与最短波长(λmean)的关系是
A.λmean=3λmin
B.λmean=5λmin
C.λmean=2λmin
D.λmean=5λmin
E.λmean=λmin
x线平均波长(λmean)与最短波长(λmin)的 关系是A.λmean =3λminB.λmean =2.5λminx线平均波长(λmean)与最短波长(λmin)的 关系是A.λmean =3λminB.λmean =2.5λminC.λmean =2λminD.λmean =l.5λminE.λmean=λmin
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在标准正态分布条件下,有()。注:(mean(x)、Me、Mo分别代表x算术平均数,中位数与众数)A.mean(x)=Me=MoB.mean(x)<Me<MoC.mean(x)>Mo>MeD.mean(x)
已知Lxx=∑(x-mean(x))2=400,Lyy=∑(y-mean(y))2=3000,Lxy=∑(x-mean(x))·(y-mean(y))=-1000;则相关系数r=()。注:mean(x)、mean(y)分别为x,y的均值。A.0.925B.-0.913C.0.957D.0.913
X线平均波长(λmean)与最短波长(λmin)的关系,正确的是A、λmean=3.5λminB、λmean=3.2λminC、λmean=2.8λminD、λmean=2.5λminE、λmean=2.2λmin
X线平均波长(λmean)与最短波长(λmin)的关系是A.λmean=3λminB.λmean=2.5λminC.λmean=2λminD.λmean=1.5λminE.λmean=λmin
X线平均波长(λmax)与最短波长(λmax)的关系,正确的是A.λmean=3.5λminB.λmean=3.2λminC.λmean=2.8λminD.λmean=2.5λminE.λmean=2.2λmin
X线平均波长与最短波长(Xo)的关系是A.λmean=0.5λ0B.λmean=1.0λ0C.λmean=2.0λ0D.λmean=2.5λ0E.λmean=3.5λ0