3.设 Xgeqslant 0,Ygeqslant 0 =dfrac (1)(5) Xgeqslant 0 =P Ygeqslant 0 =dfrac (2
已知随机变量X的分布律为-|||-x 2 3 4 9-|||-p dfrac (1)(8) dfrac (5)(8) dfrac (1)(8) dfrac (1
(Xgeqslant 0)=P(Ygeqslant 0)=dfrac (4)(7),-|||-则 max(X,Y)geqslant 0 = __设 X 和Y
.dfrac (1)(9) .dfrac (1)(18)-|||-1 .dfrac (1)(3) . α β-|||-且X,Y相互独立,求参数α,β的值。
例3.2 计算曲面积分 (int )_(dfrac {1)(2)}^x(y)_(x)zdxdy 其中∑是球面 ^2+(y)^2+(z)^2=1(xgeqslan
3.设A,B是两个事件,且 (A)=dfrac (1)(3), (B)=dfrac (1)(2), 试在下列三种情况下,求P(AB),-|||-(1) (AB)
X~B ( 2,p ),Y~B ( 3,p ),若P(X geqslant 1)=dfrac(5)(9),试求P(Y geqslant 1).$X$~$B\le
[题目]已知 (A)=dfrac (1)(2)-|||-(1)若A,B互不相容,求P(AB);-|||-(2)若 (AB)=dfrac (1)(8) 求P(AB
证明:ln dfrac (1+x)(1-x)+cos xgeqslant 1+dfrac ({x)^2}(2) -1lt xlt 1.证明:.
求 (int )_(0)^8dfrac (1)(1+sqrt [3]{x)}dx