23、 图路-|||-设矩阵A= -2 0 0 7 1 -3 0 -1 -4 1 B= [ dfrac -|||-A |-dfrac (1)(6)(A)^3(B)^r|=((-dfrac {1)(6))}^3|A(|)^3|B|=-12-|||-B |(A)^-1(B)^T|=3-|||-C |E+(A)^-1B|=dfrac (5)(3)-|||-D |A|=6

设矩阵1 0 0-|||-=dfrac (1)(2) __ 0 2 1-|||-0 3 2，则1 0 0-|||-=dfrac (1)(2) __ 0 2 1-

[1.3]设(X,Y)的分布律为-|||-Y 1 2 3-|||-X-|||--1 dfrac (1)(3) dfrac (a)(6) dfrac (1)(4)

dfrac ({mu )_(0)I}(pi R)(dfrac (1)(2)+dfrac (pi )(6))-|||-dfrac ({mu )_(0)I}(pi

3、设 (x,y)=arctan dfrac (x)(y), 则 (1,1)=-|||-(A)1; (B)0; (C) dfrac {1)(2),dfrac

设二维随机变量(X,Y)的分布律为-|||-Y 0 1 2-|||-0 dfrac (1)(4) 0 dfrac (1)(4)-|||-1 0 dfrac (1

0 .dfrac (1)(2) .-|||--dfrac (1)(2) . .dfrac (1)(8) .dfrac (1)(6) .dfrac (1)(24)

_(0)=2;-|||-(3) dfrac (1)({2)^2} , _(0)=-1;-|||-(4) dfrac (1)(4-3z), _(0)=1+i;-|

3.已知 (A)=dfrac (1)(3), (B|A)=dfrac (1)(4) ,(A|B)=dfrac (1)(6), 则 (Acup B)= __

. . 0 1 3-|||-p .dfrac (1)(5) .dfrac (1)(6) dfrac (1)(5) .dfrac (1)(15) dfrac (1

. . 0 1 3-|||-p .dfrac (1)(5) .dfrac (1)(6) dfrac (1)(5) .dfrac (1)(15) dfrac (1