概率论和数理统计期末考试试题及答案

A卷学年第一学期《B）考试时间：2006.1.9注意择题53共15分)A、BP(A)>0，P(B)>0P(B)0P(AB)0P(AB)P()P(AB)P()P(B)、、C(X,Y)p()P(B)pC)(6xy),0x2,0y40，其它kf(x,y)kP(XY4)X2212X与Y,pp,pp12120x,0.eyyyf(x)f(y)ppp其它.pXY1212XYZf(x)f(x)f(xF(x)是XXXa8,0x4;xf(x)1(a)1f(x)()()aafxdx00,FFa其他，X20YeX.1F(a)F(a)F(a)2F(a)18XXY(,)XYXY+1-与f(x)ex，x2EX2EY2EY2[][]EX2XEYEX[EX]EY[EY]EX2222225润502空题5,4,共分)()0.4P(B)0.3P(AB)0.4P(AB)___________P,,则.X~NY~N(UXYVXY1，4,013U,Vxx(x)()()PXaPXafX0其它U,V；a=~N(2,)X0.3{X2X1)aY+2X和YN5D(XaY2)E[(XaY2)]2，则a(n,p)E(X)8D(X)4.8,则n～B且,X……装……………订………………线………………标准答案和评分标准择1C2B3A4B5B1、、3、42计算ABBB123,,BBB12333P()P(AB)P(BP(AB)25%35%4%40%2%0.0345.分iiii1i1P(AB)P(B)25%5%25由P(B)110.03456913P(AB)P(B)iii1124dxk(,)fxydxdy1(6)1xydyk24001118924x2）(6xydy(x6x16)dxdx224242000()fzfxzx(,)，Z(z)f(x)f(zx)X与YfZXY0当z()fzZXYz()f()f(zdxedx1e;z当0z1f(zx)ZXY0()()()fxfzxzxzZXY0z0()()()10fzZfxfzxdxezzXYe(ez1z1YeX().FyYyF(y)PYy)P(e1y)P(Xy()fxXYX0,y0;1(y0ye24e1y.4y,0yedY4()fyY()FyY8(y0,.F(x)ft)x11当F(x)edtetxxt2211当F(x)[0xxttt205X~B{Xk}0.20.8,k03分k5kkXYg(X)XX35Eg(X)(){gkPXk}k0{X5{X0{X9分2[{X{X{XX~NY~N(UXYVXY1E(XY11D(XY212u~Nfu)Ue4UE(XY11D(XY212uV~N2)fu)e4VE(XYXYE(XY2X）EUV22EXEY2EX1DX(EX)(DY(EY))2EX1222210UV……学年第一学期期末考试《B》试卷（B）标准答案和评分标准择1D2B3B4A5D1、、、342计算ABBB123,,BBB12333P()P(AB)P(BP(AB)25%35%4%40%2%0.0345.分iiii1i1P(AB)P(B)35%4%8由P(B)220.034523(PABPB)()iii1124dxk(,)fxydxdy1xydy(6)1k24001118924x2）(6xydy(x6x16)dxdx224242000F(x)ft)x1211x当F(x)edtettx21F(x)[edtedt]1e当0xxttt220Ye().Fy1XYln(yF(y)PYy)P(e1y)P(Xy)fx()XYX0,y0;1(y0ye24e1y.4y,0yedY4()fyY()FyY8(y0,.5f(z)f(x,zx)，Z(z)f(x)f(zx)X与YfZXY当z0(z)f(x)f(zx)fZXYz()f()f(zdxedx1e;当0z1fzx()zZXY01e()e(e01()fzZ()()fxfzx当zzxzXY0z0()()()10fzZfxfzxdxezzXYz~NY~N(X1UXYVXYEUE(XYEXEY11DUD(XYDXDY212u~Nfu)Ue4U11EXEYEDUD(XYDXDY212uV~N2)fu)e4V）((2EXYXYEXYX22EXEY2EX1DX(EX)(DY(EY))2EX12222105X~B{Xk}0.2