Question 1133872
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"((n+1) combination 1)" is the number of ways you can choose 1 of (n+1) objects.  Obviously, that number is (n+1).<br>
Similarly, "(n combination 1)" is the number of ways you can choose 1 of n objects, which is clearly n.<br>
So ((n+1) combination 1) - (n combination 1) = (n+1)-n = 1