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P (B) ã§ããã (1)n(A), n (Aâ©B) ãæ±ããŠãããã,
n(Aâ©B)
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[1] (X, Y) = (5,1)ã®ãšã
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m
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ããã®ãå«ãé åãå©çšã
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48 2
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PA (B)=
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P(B)
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P(A)
n(A)
B
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bãåœããã®ã¯,{a O, bâ¯}, {a x, bâ¯} ã®å Žåãã
ããããã®äºè±¡ã¯äºãã«æåã§ããã æ±ãã確çã¯
P(B)=P(Aâ©B)+P(Aâ©B)=P(A)PA (B)+P(A)P(B)
10 9
7 3 3
=-
10 9 10
(2) a, b ã1æ¬ãã€åœããã®ã¯, {a, a x, bâ¯},
ax,O,b} ã®å Žåããã, ãããã®äºè±¡ã¯äºãã«æå
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a ãã¯ããããšã, bã¯åœ
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P(Aâ©BNC)
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7
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