概率论的随机变量及其分布问题 概率论 随机变量及其分布一题
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P\uff080<X<1\uff09=1/3\u5728\uff080,1\uff09\u4e0a\u79ef\u5206=1/3
P\uff083<X<6\uff09=2/9\u5728\uff083,6\uff09\u4e0a\u79ef\u5206=2/3
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绛旓細P(Y<=k)=P(1-X<=k)=P(X>=1-k)=0.25 鍥犱负P(X<=0.29)=0.75锛屾墍浠(X>=0.29)=1-0.25=0.75 鎵浠1-k=0.29 寰梜=0.71
绛旓細鏄剧劧锛孻鐨勫彇鍊艰寖鍥存槸[1锛2].Y鐨勫垎甯鍑芥暟鏄疐(y)=P(Y鈮).褰搚<1鏃讹紝F(y)=0;褰1鈮<2鏃讹紝F(y)=P(Y=1)+P(1<Y<y)=P(X鈮2)+P(1<X<y)=17/27+y^3/27-1/27;褰搚鈮2鏃讹紝F(y)=1.鐒跺悗鍐嶅啓涓涓畬鏁寸殑鍒嗗竷鍑芥暟銆
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绛旓細姹 P(Y鈮) 锛岄鍏圷鈮 鍦ㄥ钩闈腑灏辨槸鐩寸嚎y=x 涓嬮潰鐨勯儴鍒,姣斿 (2,1) 婊¤冻Y鈮锛屽苟涓斿湪鐩寸嚎y=x 涓嬮潰銆傛鏃舵眰绉垎灏辨槸姹傚湪鐩寸嚎y=x涓嬮潰閮ㄥ垎鐨勭Н鍒嗭紝鍏跺疄灏辨槸婊¤冻Y鈮銆傚洜涓哄師鏉ュ瘑搴﹀嚱鏁扮殑瀹氫箟鍩熸槸x>0,y>0锛屾墍浠ョ害鏉熸潯浠跺氨鏄竴涓笁瑙掑舰鍖哄煙锛寈>0,y>0,y鈮.鎵浠ュ鏋滃厛瀵箉绉垎鏃剁殑涓...
