带条件贝叶斯定理(三事件贝叶斯公式) P ( A ∣ B , C ) = P ( B ∣ A , C ) P ( A ∣ C ) P ( B ∣ C ) P(A|B,C)=\frac{P(B|A,C)P(A|C)}{P(B|C)} P(A∣B,C)=P(B∣C)P(B∣A,C)P(A∣C) 证明方式一 P ( A , B , C ) = P ( A ) P ( B ∣ A ) P ( C ∣ A , B ) P(A,B,C)=P(A)P(B|A)P(C|A,B) P(A,B,C)=