How to Find the Nth Term of an Arithmetic Sequence

The Organic Chemistry Tutor

This math tutorial provides a clear, step-by-step guide on solving problems involving arithmetic sequences. The instructor demonstrates two distinct types of problems: first, finding a specific term (the "nth" term) when given the starting sequence, and second, finding a specific term when given only two non-consecutive terms within the sequence. The video emphasizes understanding the core formula for arithmetic sequences and verifies answers by manually listing terms to build conceptual confidence. The content focuses on key algebraic concepts including identifying the first term (a1), calculating the common difference (d), and applying the explicit formula an = a1 + (n-1)d. The video breaks down the algebraic manipulation required to solve for unknown variables, such as working backwards to find the first term when it is not explicitly given. This resource is highly valuable for Algebra 1 and Algebra 2 classrooms. It serves as an excellent direct instruction tool or review material for students struggling with sequence formulas. The logical, paced explanation of how to bridge the gap between two distant terms (e.g., the 3rd and 7th terms) helps students visualize the "steps" or differences between numbers, reinforcing linear growth concepts essential for understanding linear functions.