Discrete Math problems: Mathematical induction - 1.Use mathematical induction to prove that 2-2*7+2*7^2-.....+2(-7)^n=(1-(-7)^n+1)/4 whenever n is a nonnegative integer.
2.Show that 1^3+2^2+....n^3=[n(n+1)/2]^2 whenever n is a positive integer.
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Using Permutations and Combinations - How many distinct nonnegative integer solutions are there to the equation x1 + x2 + x3 =7 in which x1 is greater than or equal to 3.
Discrete Math : Number of Solutions to Equations - a) Let n and r be positive integers. Explain why the number of solutions of the equation x1 + x2 + … + xn = r, where xi is a nonnegative integer for i = 1, 2, 3, …, n, equals the number of r-combinat ...