例1.7 若随机事件A,B同时发生,C 也必然发生,则下列选项必然成立的是 ()-|||-(A) (C)lt P(A)+P(B)-1 (B) (C)geqslant P(A)+P(B)-1-|||-(C) P(C)=P(AB) (D) P(C)=P(A+B)

(17) lim _(xarrow {0)^+}((dfrac {1)(x))}^tan x

已知一批产品共N件，其中M件是次品，从中有放回的抽取若干次，每次取出一件，则在一次抽取中取得次品数X的分布律为（ ）.A._(k)= 1-M/N 抽得正品 M/N 抽得次品 B._(k)= 1-M/N 抽得正品 M/N 抽得次品 C._(k)= 1-M/N 抽得正品 M/N 抽得次品 D._(k)= 1-M/N 抽得正品 M/N 抽得次品

用消元法解下列线性方程组:-|||- x1+3x2+5x3-4x4 =1, x1+3x2+2x3-2x4+x5=-1, x1-2x2+x3-x4-x5=3, x1-4x2+x3+x4-x5=3, x1+2x2+x3-x4+x5=-1;

4.设函数f(x )在x0处有n阶导数,且 '((x)_(0))=f''((x)_(0))=... =(f)^(n-1)((x)_(0))=0.-|||-^(n)((x)_(0))neq 0, 证明:-|||-(1)当n为奇数时,f(x)在x0处不取得极值;-|||-(2)当n为偶数时,f(x)在x0处取得极值,且当 ^(n)((x)_(0))lt 0 时,f(x0)为极大-|||-值,当 ^(n)((x)_(0))gt 0 时,f(x0)为极小值.

设sim N(0,1)，则随机变量sim N(0,1)的概率密度函数为()。sim N(0,1) 0. 0, & t_(m)0. & " data-width="268" data-height="71" data-size="4643" data-format="png" style="">

10个灯泡中有2个坏的,从中任取3个,设ξ是取出的3个灯泡中好灯泡的个数.-|||-(1)写出ξ的概率分布和分布函数;-|||-(2)求所取的3个灯泡中至少有2个好灯泡的概率.

__-|||-3 随机变量X的密度函数为 f(x)= ) A(x)^2,-1lt xlt 2 0, .-|||-求:(1)常数A;(2) (Xlt 0) : (3)X的分布函数F (x) (4) Y=2X+1 的概率密度-|||-(5.0分)

5.等比级数 sum_(n=0)^infty(1)/(2^n)=_____.

22.计算下列矩阵的逆矩阵.-|||-1 0 1 -4-|||-(1) -1 -3 -4 -2-|||-2 -1 4 4-|||-2 3 -3 2-|||-1 -1 -1-|||-1 -2 -1 1-|||-(2) -3 3 -4 -2-|||-0 1 -1 -1-|||-1-|||-1 1-|||-(3)-|||-:-|||-1 1 1-|||-_(1)-|||-_(2) ,A1可逆;-|||-(4)-|||-A-|||-一https:/img.zuoyebang.cc/zyb_473a9ab17d92e7aac1365a889a3fc56a.jpg+(a)_(1) 1 1-|||-(5) 1 .https:/img.zuoyebang.cc/zyb_473a9ab17d92e7aac1365a889a3fc56a.jpg+(a)_(2)-|||-1-|||-1 1 .https:/img.zuoyebang.cc/zyb_473a9ab17d92e7aac1365a889a3fc56a.jpg+(a)_(n)

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