Here are a few options for a WordPress post tag description, playing with different focuses for “根號2” (Square Root of 2) in Traditional Chinese:

**Option 1: Concise & Informative**

* **Description:** 探讨关于根號2的知识：包括 its定义、性质、计算方法及无穷不循环小数的概念。 (Explores the knowledge of the square root of 2: including its definition, properties, calculation methods, and the concept of non-repeating infinite decimals.)

**Option 2: Focus on Education & Learning**

* **Description:** 深入理解根號2，数学爱好者的必备基础知识。 了解其在数学中的重要性以及相关学习技巧。 (Delve deep into the square root of 2, an essential fundamental knowledge for math enthusiasts. Learn about its importance in mathematics and related learning techniques.)

**Option 3: Evoking Mystique & History**

* **Description:** 根號2 的发现与理解，带你探寻数字世界中的奇妙之处。 解锁古希腊数学家如何面对这个令人惊讶的无理数。(The discovery and understanding of the square root of 2, taking you on a journey to explore the wonders within the numerical world. Unlocking how ancient Greek mathematicians grappled with this surprising irrational number.)

**Option 4: Suitable for a technical blog**

* **Description:** “根號2” 相关的数学内容，例如计算，证明，性质分析，以及计算机实现方法。 (Mathematical content related to the square root of 2, such as calculations, proofs, property analysis, and computer implementation methods.)

**Option 5: Simple & direct**

* **Description:** 对根號2（根號2）的讨论，包括定义，估算和其他相关主题. (Discussion of the square root of 2, including definitions, estimations, and other related topics.)

**Key things to consider:**

* **Target Audience:** Choose the description that aligns best with your blog’s overall theme and who you intend to reach.
* **Post Content:** Make sure the description hints at the specific content of the posts you’ll be tagging with “根號2”.
* **SEO (Search Engine Optimization):** Include relevant keywords (like “根號2”, “square root,” “无理数” if applicable), but don’t stuff. Descriptions should be natural and informative.
* **Brevity:** Keep it concise. The description fields might have character limits.

Ultimately, the optimal choice depends on the context of your WordPress site and the content of your related posts. Good luck!