I had a student tasked with summing a finite geometric sequence with |r|>1, let’s say 1+2+4+8+16. He had apparently forgotten the formula for that, but knew the formula for the infinite series a/(1-r). Good enough he thinks, and sums 1+2+4+… = -1, then subtracts off the excess terms 32+64+128+… = -32, and gets the correct answer of 31.
crwth
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crwth@piefed.zipto
Ask Lemmy@lemmy.world•What nursery rhymes and playground songs were popular when you were very young?English
51·7 days agoJingle bells Jingle bells, Santa Claus is dead // GI Joe the Eskimo shot him in the head.
Row row row your boat, gently down the stream // Throw your teacher overboard and listen to her scream.
Mine eyes have seen the glory of the burning of the school // We have tortured every teacher and we’ve broken every rule.
Chinese, Japanese, Dirty knees, Look at these.
crwth@piefed.zipto
No Stupid Questions@lemmy.world•Can a puzzle with missing pieces be considered complete?English
5·12 days agoIf she’s used all the pieces and solved enough to reverse engineer the shape of all the missing pieces, then it is fully solved. If the missing pieces cannot be individually identified due to shared edges, then it is still solved, but is no longer a 1000 piece puzzle and she should only claim to have solved the 999 or 998 piece subpuzzle.
Yes, I switch between a few OTA stations. Usually just on as background noise. There’s a couple of NPR programs that I sometimes try to listen to.
crwth@piefed.zipto
Ask Lemmy@lemmy.world•If you saw a mushroom cloud, what would you say?English
4·2 months agoGet a good look. You might never see another.
I flooded a dormitory once, but I blame building maintenance for tricking me into it.
I wake up and head to the bathroom. Turn on the shower, nothing happens. Try the sink, still no water. No advance notice to the residents, but the water must have been shut off for some reason. I have a class to go to, so I turn everything “off”, get dressed, and leave. I’d forgotten that one of the sink knobs was threaded the opposite way from the standard convention, so that one was full on when the water was restored. Came back to the dorm after lunch and realized exactly what I’d done as soon as I entered the hallway and saw the maintenance man running his shop-vac outside my room. It overflowed the sink drain, and the bathroom floor drain, flowed through the dorm room, and was in the process of flooding the hallway.
I’m not at all sure it even is murder, even if she deliberately withheld medical care. I’ve seen advance directives from people who would refuse care in similar circumstances, and it’s not a crime for a wife to honor such a wish. Maybe you could get her on lying to the police about it, or for a lesser crime of medical neglect, but not murder.
If you really want it to be a prosecutable murder, find her fingerprints on a bottle of the virus she poisoned him with. Take a blood sample to test for antiviral treatments she took to prevent accidently infecting herself. Maybe find her impatient boyfriend who didn’t want to wait for a divorce.


Indeed, and would have earned full marks had he said that, or even showed any awareness that his intermediate results were somehow nonstandard.