Hi to everyone.
I am glad to announce that I am going to put an A++ mark on your end-course Maths qualification if you find an integer verifying to be a perfect square ending in "7".
If not... ...I will have enough if it finishes in "8" instead of "7"!
Still no luck? well, perhaps you should try with "2" or "3"!.
By the way... ...Why am I so sure that none of you are going to be able to find perfect squares ending with 2, 3, 7 or 8?
(Of course, it's impossible, if you don't believe me, just keep on searching... ...and get bored! ;D)
If someone explains it fine... ...I will consider for a good mark. (This time is no joke).
Send me an e-mail before posting anything. If someone posts a right answer directly, following ones won't have the opportunity to do the same.
Good luck and think a bit.
RAFA.
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ReplyDeleteÁlvaro have sent me one good idea about my question, but he has something left to explain... ...he almost get it, so hurry up!
ReplyDeleteJavier has misunderstood the question: "perfect square" here refers to a integer number, it has no geometrical approach, so this matter is not about quadrilaterals, but numbers instead.
I encourage you to think about. First step is always trying to see what happens in simple cases...
Alvaro has sent a very complete response explaining the question very well. I will wait until Friday to post the solution.
ReplyDeleteBlanca's approach is correct too.
Rafa Díaz is a bit far from an explanation. The question, set up in a direct way would be:
ReplyDeleteWhy does a perfect square always end with a digit different from "2", or "3", or "7", or "8"?