+0  
 
0
398
5
avatar

Is it possible to find the square root of an number without a calculator.

Guest Oct 17, 2014

Best Answer 

 #2
avatar+85794 
+8

There are probably many methods........you can read about a couple of them here......http://mathforum.org/dr.math/faq/faq.sqrt.by.hand.html

(Be sure to scroll to the bottom of the page for some links to others.....)

 

CPhill  Oct 17, 2014
Sort: 

5+0 Answers

 #1
avatar+24 
+5

i dont know i belive it would be very hard to do that though it would take a math wiz

thelonewolf  Oct 17, 2014
 #2
avatar+85794 
+8
Best Answer

There are probably many methods........you can read about a couple of them here......http://mathforum.org/dr.math/faq/faq.sqrt.by.hand.html

(Be sure to scroll to the bottom of the page for some links to others.....)

 

CPhill  Oct 17, 2014
 #3
avatar
+5

Yes, one approach is to use a divide and average approach.

Example: $$\sqrt{3}$$

Guess an approximate answer, say 2. 

  • Divide to obtain 3/2 = 1.5 and average to obtain (2 + 1.5)/2 = 1.75.
  • Divide to obtain 3/1.75 = 1.71428 and average to obtain (1.75 +  1.71428)/2 = 1.73214
  • Divide to obtain 3/1.73214 = 1.73196 and average to obtain (1.73214 + 1.73196)/2 = 1.73205

This is already close to the value provided by a calculator and becomes even more accurate if you use more decimal places and repeat the divide and average a few more times.  This method was known for thousands of years.

Guest Oct 17, 2014
 #4
avatar+17721 
+5

Before the creation of hand-held calculators, an algorithm was taught in algebra classes; it can be found at 

http://www.basic-mathematics.com/square-root-algorithm.html

geno3141  Oct 17, 2014
 #5
avatar+85794 
+5

Notice that the "divide and average" method is very simple.......the only problem with the method - and some others, as well - is that the numbers generated are difficult to work with........unless you have a calculator......!!!!

 

CPhill  Oct 17, 2014

25 Online Users

avatar
avatar
avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details