设随机变量X~B(3,0.3),且Y=X^2,则P{Y=4}= 设随机变量X~B(3,0.6),且Y=(X(3-X))/2,...

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P{X=i}=(3Ci)(0.3^i)(1-0.3)^i (i=0,1,2,3)
概率分布如下
X | 0 1 2 3
P | 0.343 0.441 0.189 0.027

Y=X^2=4 即X=2 ,P{Y=4}= P{X=2}=0.189

璁鹃殢鏈哄彉閲廥~B(3,0.2),浠=X^2,鍒橮(Y=4)=___.姹傝缁嗚В绛旇繃绋嬨俖鐧惧害鐭 ...
绛旓細X | 0 1 2 3 P | 0.343 0.441 0.189 0.027 Y=X^2=4 鍗砐=2 ,P{Y=4}= P{X=2}=0.189

璁鹃殢鏈哄彉閲廥~B(3,0.2),浠=X^2,鍒橮(Y=4)=___.姹傝缁嗚В绛旇繃绋嬨俖鐧惧害鐭 ...
绛旓細x鏈嶄粠浜岄」鍒嗗竷锛氭墍浠锛圷=4锛=P锛坸=2锛=3*0.2²*0.8=0.096

璁鹃殢鏈哄彉閲弜~b(3,0.2),涓旈殢鏈哄彉閲廦=X(3-X)/2,鍒橮(Y=0)=
绛旓細P(Y=0)=P(X=3)+P(X=0)=0.2^3+0.8^3=0.52婊℃剰璇峰ソ璇勫摝锛屾垜姒傜巼璁鸿冨畬浜嗭紝鍢诲樆锛岀浣犺冭瘯椤哄埄鍟

璁鹃殢鏈哄彉閲廥~B(3,0.4),涓旈殢鏈哄彉閲廦=(3-X)/2,鍒橢(Y)=
绛旓細E(X)=3脳0.4=1.2 E(Y)=3/2-1/2路E(X)=1.5-0.6=0.9 銆愰檮娉ㄣ戯紙1锛塜~B(n,p),鍒 E(X)=np 锛2锛塃(kX+b)=kE(X)+b

璁鹃殢鏈哄彉閲廥锝b(3,0.1),鍒橮(X鈮1)=?姹傝В!
绛旓細P(x鈮1) = 1-P(x<1) = 1-P(x=0)鑰孭(x=0)=(1-0.1)³=0.9³=0.729 鈭碢(x鈮1)=1-0.729=0.271

璁鹃殢鏈哄彉閲廥~B(3,0.4),涓旈殢鏈哄彉閲廦=(3-X)/2,鍒橢(Y)=
绛旓細E(X)=3脳0.4=1.2 E(Y)=3/2-1/2路E(X)=1.5-0.6=0.9 銆愰檮娉ㄣ戯紙1锛塜~B(n锛宲)锛屽垯 E(X)=np 锛2锛塃(kX+b)=kE(X)+b

璁鹃殢鏈哄彉閲廥~B(3,0.4),姹侾{X鈮1}
绛旓細X灞炰簬n锛3,p锛0.4鐨勪簩椤瑰垎甯冿紝鎵浠{X锛0}锛0.6^3锛0.216 P{X鈮1}锛1-P{X锛0}锛0.784 鍥炵瓟瀹屾瘯姹傞噰绾

璁鹃殢鏈哄彉閲廥~B(3,0.2),鍒橮{X>2}鏄灏?
绛旓細P(X>2)=P(X=3)=0.2^3=0.008

闅忔満鍙橀噺X~b(3,0.4)琛ㄧず浠涔 ? 杩欎釜寮忓瓙琛ㄧず浠涔堟剰鎬濆晩 ~~姹傛暀~~
绛旓細X鏈嶄粠鍙傛暟涓3,0.4鐨凚ernoulli鍒嗗竷 鍗冲湪3娆＄嫭绔嬮噸澶嶈瘯楠屼腑,姣忔璇曢獙鎴愬姛鐨勬鐜囦负0.4,鎬荤殑鎴愬姛娆℃暟涓X鐨鍒嗗竷 P(X=k)=C(3,k)*0.4^k*0.6^(3-k)

璁鹃殢鏈哄彉閲廥~B(3,0.4),鍒橮(X=0)=
绛旓細鍥炵瓟锛0.6浜岄」鍒嗗竷涓嶆槸杩欎釜灏辨槸閭ｄ釜,鍙湁涓ょ缁撴灉

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