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Homework Help: How to prove the following

  1. Sep 13, 2010 #1
    1)given that: (1+x)^n=summation nCk X^K

    PROVE: SUMMATION nCk p^k q^n-k =1, where p+q=1
    2) prove the general law of addition: P(E1 U E2 U.....U En)=sum P(Ei)-sum P(EiEj)+sum P(EiEjEk)-.....(-1)^n-1 P(E1E2....En)
     
  2. jcsd
  3. Sep 13, 2010 #2

    mathman

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    For 1:
    1=(p+q)n=qn(1+(p/q))n=qnΣnCk(p/q)k=ΣnCkpkqn-k
     
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