Challenge: can you take the sqrt (n) using only one operation

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Discussion Overview

The discussion revolves around the challenge of calculating the square root of a number using only one operation, exploring various algorithms and methods, including the Babylonian method. Participants debate the feasibility of achieving this goal and the implications of using different operations.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants note that the Babylonian method requires three operations per iteration and question whether a simpler or faster algorithm exists.
  • One participant suggests that applying the square root operation directly constitutes a single operation, but others challenge this interpretation.
  • Another participant proposes that if the solution is known, one division operation could yield the square root, but this assumes prior knowledge of the result.
  • There is a discussion about the use of limits and comparison operations (e.g., '<') in the context of finding square roots, with some arguing that these concepts are essential for certain calculations.
  • Some participants express skepticism about the possibility of finding a method that requires only one operation, emphasizing that it may not be feasible in general.
  • One participant highlights the practical aspect of the problem, suggesting that any new method should be more convenient for manual calculations.
  • There is mention of the need to stop calculations after a certain number of digits for practical purposes, with examples provided to illustrate this point.
  • Confusion arises regarding the interpretation of "one operation," with participants clarifying their understanding of the challenge and its constraints.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether it is possible to calculate the square root using only one operation. Multiple competing views remain regarding the definitions and implications of "one operation."

Contextual Notes

Some participants note that certain mathematical operations may be necessary to achieve the desired precision, and there are unresolved questions about the limitations of using only basic operations. The discussion also reflects varying interpretations of what constitutes a single operation.

  • #31
It can be done in one step provided you specify the precision in advance.

You use the number as the index into an array containing the root. As long as the precision is specified, each real number is represented by an integer. Most modern computers will perform the indexed register load as an atomic operation (single step).
 
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  • #32
Mark44 said:
Did you mean "viewers"?
I'm of courteous disposition and act my age, do you expect a reply?

I suggested: (edited OP)
The best known algorithm EDIT: i.e. iterative method ('Babylonian') to take the square root of a number requires 3 operations...
Do you know a simpler or faster one?
Can you find a method that requires only 1 operation? (No = 1)

EDIT : a [square]root is found with Nt ops., iterating Ni times a formula that requires No ops. using N+ different op-signs. Nt = Ni * No.
Babylonian method
, \sqrt{354.045^2}, ( if x0 = 300.00) : N+=No = 3, Ni = 4 , 3 * 4 \rightarrow Nt = 12 operations
if No = 1 \rightarrow (N+ = 1, Nt = Ni); [in the title: N+ = 1 \rightarrow No = 1 , Nt < 12] ;
Nt < 8 is a 'good' solution, (5 * 1) = 5 operations would be 'brilliant'.
Post #31 proves that new readers can't carefully examine all previous posts. An edit to the OP would probably help. Thanks.
 
Last edited:

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