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Calculate the Nth Term

Arithmetic Sequence Formula:

\[ a_n = a_1 + (n-1)d \]

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1. What is an Arithmetic Sequence?

An arithmetic sequence is a sequence of numbers in which the difference between consecutive terms is constant. This constant difference is called the "common difference."

2. How Does the Calculator Work?

The calculator uses the arithmetic sequence formula:

\[ a_n = a_1 + (n-1)d \]

Where:

Explanation: The formula calculates any term in an arithmetic sequence by starting with the first term and adding the common difference multiplied by one less than the term position.

3. Applications of Arithmetic Sequences

Details: Arithmetic sequences are used in various fields including finance (calculating simple interest), physics (uniform motion), computer science (algorithm analysis), and everyday situations like calculating seating arrangements or savings patterns.

4. Using the Calculator

Tips: Enter the first term of the sequence, the common difference between terms, and the position of the term you want to find. All values must be valid numbers with n being a positive integer.

5. Frequently Asked Questions (FAQ)

Q1: What if the common difference is negative?
A: A negative common difference means the sequence is decreasing. The formula works the same way regardless of whether d is positive or negative.

Q2: Can n be a decimal or fraction?
A: No, n must be a positive integer as it represents the position of a term in the sequence (1st, 2nd, 3rd, etc.).

Q3: What's the difference between arithmetic and geometric sequences?
A: In arithmetic sequences, the difference between terms is constant. In geometric sequences, the ratio between terms is constant.

Q4: How do I find the sum of an arithmetic sequence?
A: The sum of the first n terms can be calculated using the formula: \( S_n = \frac{n}{2}(a_1 + a_n) \) or \( S_n = \frac{n}{2}[2a_1 + (n-1)d] \).

Q5: Can this formula be used for non-integer sequences?
A: Yes, the first term and common difference can be any real numbers (integers, fractions, decimals), creating sequences with non-integer terms.

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