(请小数点之后保留2位有效数字,u_(0.025)=1.96)23.(填空题,4.0分)已知总体$X\sim N(\mu,4)$,从总体中抽取容量n=16的样本
4、设X_(1),X_(2),...,X_(16)是来自正态总体N(mu,1)的样本,得样本均值为overline(x)=5.20,求mu的置信水平为0.95的
A)(overline(X)-u_((alpha)/(2))(4)/(sqrt(n)),overline(X)+u_((alpha)/(2))(4)/(sqrt
二次型f(x_(1),x_(2),x_(3))=x_(1)^2+4x_(2)^2+4x_(3)^2+2lambda x_(1)x_(2)-2x_(1)x_(3)
已知实二次型f(x_(1),x_(2),x_(3))=x_(1)^2+4x_(2)^2+4x_(3)^2+2lambda x_(1)x_(2)-2x_(1)x_
A)(overline(X) - u_(alpha) (2)/(sqrt(n)), overline(X) + u_(alpha) (2)/(sqrt(n))
3.设 approx N(0,(4)^2), approx N(1,(3)^2), 且 (rho )_(x)=-dfrac (1)(2), 令 =dfrac (
4.10 设随机变量X 1,X2,X3相互独立,且 _(1)approx B(4,dfrac (1)(2)) _(2)approx B(6,dfrac (1)(
实 二 次 型 f(x_(1),x_(2),x_(3))=3x_(1)^2+4x_(1)x_(2)+4x_(2)^2-4x_(2)x_(3)+5x_(3)^2是
随机变量 approx B(n,p) ((X)^-2)=0 approx B(n,p) ((X)^-2)=0approx B(n,p) ((X)^-2)=0a