Priya says any number's cube is always bigger than its square, since cubing involves one extra…
Priya says any number's cube is always bigger than its square, since cubing involves one extra multiplication. Is that true for every whole number?
Who do you think is right? Pick one.
The answer: No, this is not true for every number
Why
Priya's reasoning holds up for most numbers you'd think to check — 2³=8 is indeed bigger than 2²=4, and 5³=125 dwarfs 5²=25, so 'one extra multiplication should make it bigger' seems to check out every time she tries a normal-sized number. Test the very smallest whole numbers, though, and the rule quietly breaks: for n=1, the cube is 1×1×1=1, and the square is 1×1=1 — exactly EQUAL, not bigger. For n=0, both the cube and the square are 0 — equal again, not bigger. Cubing does add an extra multiplication, but multiplying by 1 (or by 0) doesn't grow a number the way multiplying by 2, 5, or 10 does, which is exactly why the extra step makes no difference right at these two special values. Test: line up n, n², and n³ for n=0,1,2,3 side by side — 0,0,0 then 1,1,1 then 2,4,8 then 3,9,27 — and watch the cube only pull ahead of the square starting from n=2 onward. No, this is not true for every number: it holds for every whole number 2 and above, but fails right at 0 and 1, where cube and square come out exactly equal.
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