3 ms·
> 2 also seems to rely on a trick Pretty sure students are supposed to switch( n % 3 ), and solve for all 3 possible values of the remainder. > probably just
by Const-me 5y ago
> 2 also seems to rely on a trick
Pretty sure students are supposed to switch( n % 3 ), and solve for all 3 possible values of the remainder.
> probably just trying out numbers
You can't solve a 4-degree polynomial equation by trying out numbers. It has up to 4 solutions, not guaranteed to be real, let alone rational or integer.
- dmurray 5y ago> You can't solve a 4-degree polynomial equation by trying out numbers On the contrary, in practice you can't solve them any other way! Spot a simple factorization or guess a root is your best chance if you don't fancy working through the quartic formula [0], which will take you multiple pages just to write down the first step, and a numeric approximate solution is not acceptable. [0] https://math.stackexchange.com/a/1135224 https://math.stackexchange.com/a/1135224