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Discrete Math: Sequences and Induction

The value of a new car in 2015 was $40,000. It depreciates 7% each year. How much will the car be worth in 2024?

John bought a new home in 2002. The value of the home increases 4% each year. If the price of the house is $225,000 in 2015, how much did he pay for it in 2002?

A sample contains 100 counts of bacteria. The bacteria triples every 15 minutes. How much bacteria will there be in 1 hour?

Prove that for any integer n>4n > 4, n!>2nn! > 2^n.

Prove that n!>2nn! > 2^n for n4n \geq 4 using mathematical induction.

Prove that 1+2+3++n=n(n+1)21 + 2 + 3 + \ldots + n = \frac{n(n+1)}{2} using mathematical induction.

Show that 1+2++n=n(n+1)21 + 2 + \ldots + n = \frac{n(n + 1)}{2}.

Prove by induction that the sum of the series r=1nr2\sum_{r=1}^{n} r^2 is equal to n(n+1)(2n+1)6\frac{n(n+1)(2n+1)}{6}.

Prove that the sum of the squares of the first nn natural numbers can be expressed as: 12+22+32++n2=n(n+1)(2n+1)61^2 + 2^2 + 3^2 + \cdots + n^2 = \frac{n(n+1)(2n+1)}{6} for all natural numbers n1n \geq 1 using proof by induction.

Define the nth number ana_n in a Fibonacci sequence such that an=an1+an2a_n = a_{n-1} + a_{n-2} for n2n \geq 2, with initial conditions a0=0a_0 = 0 and a1=1a_1 = 1.

For the sequence defined by 0,2,6,12,20,30,420, 2, 6, 12, 20, 30, 42, show that anan1=2na_n - a_{n-1} = 2n and prove that an=n(n+1)a_n = n(n+1) given a0=0a_0 = 0.

Find the sum of n2n^2 from n=1n = 1 to n=5n = 5.

Find the sum of 2n2^n from n=1n = 1 to n=6n = 6.

Find the sum of 3n+23n + 2 from n=1n = 1 to n=5n = 5.

Find the sum of the first 100 terms of the sequence given by 4n+54n + 5.

Calculate the sum of the first four terms of the sequence given by 32n1\frac{3}{2}^{n-1}.

Determine the sum of the infinite geometric sequence represented by 8(23)n18 \left( \frac{2}{3} \right)^{n-1}.