Some help with the following would be appreciated!
Find (and prove) a formula for Σ from j=1 to k of j^3
Known propositions:
Σ from j=1 to k of j = k(k+1) / 2
Σ from j=1 to k of j^2 = k(k+1)(2k+1) / 6
Thank you!
Helolo, jstarks44444!
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We note that: .
Let
And we have this "stack" of equations:
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Add the entire stack of equations and we have:
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Substitute the known formulas:
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Then we have:
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