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    Module 0 Day 16 Challenge Part 3
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      genuineopossum M0★ M1★ M2★ M3★ M5★
      last edited by

      Is there a reason why the last digits of the squares of the numbers from 1-9 form a palindrome? (149656941) I'm just curious

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        fantasticcrow M0 M1★ M3 M5
        last edited by

        hello! it's because you can think of 9 as (10-1), 8 as (10-2) and so on. so basically, if numbers 1-4 are "x" then numbers 6-9 are "10-x". and if you expand (10-x)^2, you'll find that it's 10^2-20x+x^2 and so the last digit of (10-x)^2 is just going to be the same as the last digit of x^2. hope that helped.😁

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          fantasticcrow M0 M1★ M3 M5 @fantasticcrow
          last edited by

          @genuineopossum to clarify, 9 is supposed to be (10-x) for 1 and 8is supposed to be (10-x) for 2 and so on.

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