几何级数 (jī) — geometric progression; geometric series

Définition

Exemples

• 这个几何级数增长得很快，每个数是前一个数的两倍。
  Zhè ge jī zēng zhǎng dé hěn kuài, měi gè shù shì qián yí gè shù de liǎng bèi.
  This geometric progression grows very fast; each number is twice the previous one.
• 计算几何级数前n项和的公式是S=a(1-r^n)/(1-r)。
  Jì suàn jī qián n xiàng hé de gōng shì shì S=a (1-r^n) / (1-r).
  The formula for the sum of the first n terms of a geometric series is S=a(1-r^n)/(1-r).
• 几何级数和算术级数不一样，它是按固定比例增加的。
  jī Hé suàn shù jí shù bù yí yàng, tā shì àn gù dìng bǐ lì zēng jiā de.
  Geometric progressions are different from arithmetic progressions; they increase by a fixed ratio.