# My son taught me two Math tricks!

in STEEM CN/中文last year (edited)

View this post at Steemit: https://steemit.com/@justyy/my-son-taught-me-two-math-tricks

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last year (edited)

Great trick! @justyy
I got another. (I don't speak good english so excuse me if there is something I don't say right). The rule is: The sum of odds numbers in sequence starting at 1 is equal to the square of the quantity of numbers you summed.
There is the list for you to check:
1-----------1^2
1+3-------2^2
1+3+5---3^2
So if you want to see how much is 9^2 you just sum nine odds numbers in sequence starting at 1...
9^2=1+3+5+7+9+11+13+15+17(Nine odds nubers in sequence starting at 1).
It matches at any quantity you try.
Enjoy!

Thank you very much. It is very interesting! Loving it.