Daily Maths Challenges

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submitted 9 months ago by siriusmart to c/dailymaths

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Show that the sum of the first n squares is n(n+1)(2n+1)/6.
I know this is often in the textbook for proof by induction, which is why proof by induction is not allowed.

This is a relatively hard one, take your time.

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[–] siriusmart 3 points 9 months ago* (last edited 9 months ago)

Hint:

spoiler

It is often helpful to visualise the problem, build it in minecraft to see if u notice anything.

Note that the sum of first n natural numbers can be proven without induction, as shown below

Solutions:

spoiler