Discrete Math

[solemn sonnet]

I don't understand how this is wrong.

[charred trench]

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[reef dust]

(a) and (c) are correct.
(b): note that the sum of first k-th powers is around n^(k + 1)/(k + 1). So, 9 is too much for seventh powers.
(d): why not -6?

[solemn sonnet]

Ty I figured it out b) was 8

[reef dust]

Right, yeah.

[proper pagoda]

@solemn sonnet

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