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For readers interested in pythagorean triplets with Consecutive natural numbers, take any odd number -- say 11 -- and square It. 11 squared = 121 = 2(60)+ 1. Add 60 squared to both sides to get 11 squared + 60 squared = 60 squared + 2(60) + 1 = (60 + 1) squared = 61 squared. What do we get? (11, 60, 61). Works every time. Prove it For a general case.

  
Total Answers and Comments: 3 Last Update: May 16, 2006   
  
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August 10, 2005 18:28:58   #1  
Vasanth        

RE: For readers interested in pythagorean triplets with Consecutive natural numbers, take any odd number...
Two numbers, say a & b, form Pythogeran triplets, if  
 
a^2 + b^2 = (b+1)^2 
 
=> a^2 + b^2 = b^2 + 2b + 1 
 
=> a^2 = 2b - 1 
 
=> b = (a^2 - 1) / 2 
 
for (a^2 - 1) to be divisible by 2, a^2 should be odd and hence "a" should be odd. 
 
For every a = 3, 5, 7, 9, 11, .... we will have a "b" and "b+1" which form Pythagorean triplets. 
 
Ex: 3, 4, 5 
5, 12, 13 
7, 24, 25 
9, 40, 41 
11, 60, 61 
13, 84, 85 
 
...

 
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August 27, 2005 13:33:21   #2  
Radeesh        

RE: For readers interested in pythagorean triplets with Consecutive natural numbers, take any odd number...
Two numbers, say m & n, form Pythogeran triplets, if  
n=11 and m=60 
First condition n^2 + m^2 = (m+1)^2  
11^2+60^2=(60+1)^2 
Second condition n^2=2m+1 
11^2=2(60)+1 
So if we prove first condition to second the this must be true. 
Consider Second condition n^2=2m+1 
add m^2 on both sides 
n^2+m^2=m^2+2m+1 
n^2+m^2=(m+1)^2 

 
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May 16, 2006 10:21:02   #3  
C. Sivasankaran        

RE: For readers interested in pythagorean triplets wit...

There are some other ways also

1.  Multiples of the Odd number triplets, say for example 3, 4, 5

     Its multiples also triplets i.e. 6,8,10 ;   9, 12, 15  ;  12, 16, 20 ; 15, 20, 25

2.  It can be extended to  even numbers also

    4^2 = 16 , then divide by 4 we get 4, 4-1 and 4+1 are its sets. By this method we can get

    4, 3,  5

    6, 8,  10

    8, 15,  17

    10, 24, 26

    12, 35,  37  and so on...

3.  Simillarlly we can divide a square number by 6 and subtracting and adding by 1.5 we get the triplets.  By this we can get the following.

91215
153639
217275
27120123
33180183
39252255
45336339
     and so on...


 
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