use mathematical induction to prove that each proposition is valid for all positive integral values of n:
1. 3+9+15+...+(6n-3)=3n^2
2. 5^n - 1 is divisible by 4
find each value:
1. P(9,6)
2. P(7,4)
3. C(8,2)
4. C(6,5)
Throw in a word problem...
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