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    The bit underlined in red. What is going on?
    Name:  bino.PNG
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    (Original post by scientific222)
    The bit underlined in red. What is going on?
    Name:  bino.PNG
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    Not sure what you do not understand

    (n-2)! = (n-2) x (n-3)!

    Since (n-2)! = (n-2)(n-3)(n-4)(n-5) ... ... ... ...

    And (n-3)! = (n-3)(n-4)(n-5) ... ... ... ...
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    (Original post by TenOfThem)
    Not sure what you do not understand

    (n-2)! = (n-2) x (n-3)!

    Since (n-2)! = (n-2)(n-3)(n-4)(n-5) ... ... ... ...

    And (n-3)! = (n-3)(n-4)(n-5) ... ... ... ...
    I understand now thank you. I previously didn't understand the use of variables in factorials , it was the first time I came across it
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    (Original post by scientific222)
    I previously didn't understand the use of variables in factorials , it was the first time I came across it
    Ah .. ok

    Glad to have helped
 
 
 
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