Question

prove sigma n^2=n(n+1)(2n+1)/6

Answer 1

i know!

Answer 2

that is \[\sum_{1}^{n}\]n^2

Answer 3

then tell?

Answer 4

NCERT

Answer 5

For reference, you should not use the same variable for the upper limit as you do in the expression. Instead, say
\[ \sum_{k=1}^n\space k^2 \]

Answer 6

Do you mean prove it or derive it? It can be proved with induction.

Answer 7

sorry i meant derive it?

Answer 8

http://www.trans4mind.com/personal_development/mathematics/series/sumNaturalSquares.htm

In the first proof I don't get this part "...Because \(Δ_3\) is a constant, the sum is a cubic of the form..."