とね日記

理数系ネタ、パソコン、フランス語の話が中心。
量子テレポーテーションや超弦理論の理解を目指して勉強を続けています!

Square root 2,401 using abacus (Half-multiplication table method 3)

2017年12月24日 18時08分20秒 | 開平、開立
[Set 2,401 on Mr. Square root]


[Japanese]

We will continue from where we ended in the last article, the actual solutions to calculate Square root using abacus. Today's example is Half-multiplication table method (Hankuku method), root is 2-digits case. We require 9 as root in the middle of calculation. Please check the Theory page for your reference. You can check the Index page of all articles.

Square root methods: Double-root method, Double-root alternative method, half-multiplication table method, half-multiplication table alternative method, multiplication-subtraction method, constant number method, etc.


Abacus steps to solve Square root of 2,401 (Answer is 49)

"1st group number" is the left most numbers in the 2-digits groups of the given number for square root calculation. Number of groups is the number of digits of the Square root.

2,401 -> (24|01) : 24 is the 1st group number. The root digits is 2.


Step 1: Place 2401 on CDEF.


Step 2: The 1st group is 24.


Step 3: Square number ≦ 24 is 16=4^2. Place 4 on B as the 1st root.


Step 4: Subtract 4^2 from the 1st group 24. Place 24-4^2=08 on CD.


Step 5: Focus on 801 on DEF.


Step 6: Divide 801 by 2. Place 4005 on DEFG.


Step 7: Divide 40 on DE by the current root 4.


Step 8: 40/4=9 remainder 4. Place 9 on C as 2nd root.


Step 9: Place remainder 04 on DE.


Step 10: Focus on 405 on EFG.


Step 11: Subtract 2nd root^2/2 from 405 on EFG. Place 000 on EFG.


Step 12: Square root of 2401 is 49.


Final state: Answer 49

Abacus state transition. (Click to Zoom)



Next article is also about Half-multiplication table method, more difficult example.


Related articles:

How to solve Cube root of 1729.03 using abacus? (Feynman v.s. Abacus man)
http://blog.goo.ne.jp/ktonegaw/e/cff5d6e7ecaa07230b9cc7af10b23aed

Index: Square root and Cube root using Abacus
http://blog.goo.ne.jp/ktonegaw/e/f62fb31b6a3a0417ec5d33591249451b


Please place your mouse on the buttons and click one by one. These are blog ranking sites.
にほんブログ村 科学ブログ 物理学へ 人気ブログランキングへ 
コメント    この記事についてブログを書く
  • X
  • Facebookでシェアする
  • はてなブックマークに追加する
  • LINEでシェアする
« くすりの科学知識 (ニュート... | トップ | 開平と開立(第33回):2,401... »

コメントを投稿

ブログ作成者から承認されるまでコメントは反映されません。

開平、開立」カテゴリの最新記事