Originally Posted by 22B
Thanks, ColinsMum. I think he's over the "injustice" now. (He understood there was an exact syntax to follow, even if he didn't know where it came from, but his clumsy keyboard skills tripped him up (twice).) Anyway, Alcumus is free, so we can live with it's strict answer checker. I've never seen Alcumus make an error, unlike most other applications I've seen.
We've seen quite a few! But if you report them, the reports get read promptly by humans. (We've seen mistakes in solutions, including one really bizarre one that began with an arithmetic error and got worse from there, more often than nonsensical questions, and I don't recall a blatant "right answer marked wrong" case.)

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