等差数列(AP)の第 1 項、第 10 項、および第 n 項を見つけます。
Finding n in an Arithmetic Sequence Given are Sn, a1, an or Sn, a1, d.
How To Find The Nth Term of an Arithmetic Sequence
Finding “n” or the Term’s Position in the Arithmetic Sequence
Find n in an arithmetic sequence
数列のn番目の項を見つける
Arithmetic Sequences and Arithmetic Series - Basic Introduction
GCSE数学 - 等差数列のn項の式の書き方(2026/27年度試験)
Writing a General Formula of an Arithmetic Sequence
💯 Finding the Number of Terms of Arithmetic Sequences Explained
Arithmetic Sequence (Explicit Formula)
Learn How to Find the nth Term of an Arithmetic Sequence Example with 2, 6, 10, 14, ...
主要スキル - 等差数列のn番目の項の式を決定する