SOLUTION: Help pls 😊
Triangular numbers are: 1,3,6,10....where the nth such number is n(n-1)/2. Show that the sum of two consecutive triangular numbers is a square number.
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Triangular numbers are: 1,3,6,10....where the nth such number is n(n-1)/2. Show that the sum of two consecutive triangular numbers is a square number.
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Question 985848: Help pls 😊
Triangular numbers are: 1,3,6,10....where the nth such number is n(n-1)/2. Show that the sum of two consecutive triangular numbers is a square number. Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! Triangular numbers are: 1,3,6,10....where the nth such number is n(n-1)/2. Show that the sum of two consecutive triangular numbers is a square number.
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n(n-1)/2 + (n+1)*n/2 = (n^2-n + n^2+n)/2
= 2n^2/2
= n^2
