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#1 2017-05-30 00:22:51
- Zeeshan 01
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- Registered: 2016-07-22
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Square root
Hi;
How to take square root of number like 0.2, 0.34,0.23455 etc without calculator
Sqrt of 0.2 is ???
0.707 multiple b 0.707
Malik
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#2 2017-05-31 03:02:28
- Bob
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Re: Square root
hi Zeeshan 01
If you google "square root without a calculator" you'll find loads of sites offering methods. They all need some arithmetic however. How's your long division?
A method I rather like is this:
Let's say the number is N. Take a guess for the square root, say x, and do N÷x = y.
If x was too small then y will be too big and vice versa. So work out (x+y)/2 and make this your next guess. This 'homes in' on the root quite quickly.
eg. N=50 x = 7
y = 50/7 = 7.14.....
(x+y)/2 =7.0714...
new x = 7.0714....
new y = 7.070707
new(x+y)/2 = 7.071068
This is accurate to 5 decimal places.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob 
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#3 2017-05-31 05:58:29
- Zeeshan 01
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Re: Square root
Hows your long division?
Pretty Good
Last edited by Zeeshan 01 (2017-05-31 06:00:23)
Malik
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#4 2017-05-31 06:02:10
- Zeeshan 01
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Re: Square root
Sqrt of 0.2 is ???
Can you put this info in your method??
Malik
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#5 2017-05-31 06:32:02
- Bob
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Re: Square root
here we go:
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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#6 2017-05-31 20:18:11
- Zeeshan 01
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Re: Square root
??? N is 0.2 and how x is 1 and y is 0.2
Malik
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#7 2017-05-31 21:15:05
- Bob
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Re: Square root
N is 0.2 and how x is 1 and y is 0.2
You asked for
Sqrt of 0.2 is ???
So that makes N=0.2
x is a guess. It can be any number. If you chose a value close to the correct answer, then you'll get to an accurate answer more quickly. But any number will work so I chose x = 1.
Then you calculate y using the formula y = N/x= 0.2/1 = 0.2
Then you calculate the mean average of x and y = (1+0.2)/2 = 1.2/2 = 0.6
That becomes the new x. Repeat until x and y are so close to each other that (x+y)/2 gives the same result. That's the square root.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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#8 2017-05-31 22:04:16
- Zeeshan 01
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Re: Square root
Hmm
Malik
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#9 2017-05-31 22:06:16
- Zeeshan 01
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Re: Square root
You know proportions direct and indirect??
Malik
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#10 2017-06-01 00:01:45
- iamaditya
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- Registered: 2016-11-15
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Re: Square root
Do you need help with that?
Practice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam
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#11 2017-06-02 15:19:56
- Zeeshan 01
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Re: Square root
So work out (x+y)/2 and make this your next guess
How x become (x+y)divde by 2
Malik
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#12 2017-06-03 14:40:24
- Zeeshan 01
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- Registered: 2016-07-22
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Re: Square root
How x become (x+y)divde by 2
Malik
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