When Alpha is submitted the equation $a(a^2-1)=2b^2$, it unexpectedly forgets the integer solution $a=1,b=0$. What could explain this ?
closed as off-topic by Mariusz Iwaniuk, Michael E2, Szabolcs, m_goldberg, b3m2a1 Nov 10 '18 at 17:34
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "The question is out of scope for this site. The answer to this question requires either advice from Wolfram support or the services of a professional consultant." – Mariusz Iwaniuk, Michael E2, Szabolcs, m_goldberg, b3m2a1
I have observed that the anomaly disappears when the resolution is explicitly asked over the integers (the qualifier Diophantine also works).
So it seems that the flaw would be in the logics for the "Integer solutions" section that comes along with an unspecified domain (presumably $\mathbb C$ by default). As suggested by @chiphurst, this could be because a general solver is used and might fail to find the exact integers.