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by whatshisface 2460 days ago
>Now the math department? They were a different story. No calculators. Period. Ever. Made higher-level calculus... interesting.

When I took calculus the professor made sure that every arithmetic problem could be solved quickly. The trick he used was to carefully track factors when setting up the problem, so that the numbers never got very big, and also so that things had a way of cancelling (I can't tell you how many problems had one or zero as an answer.) Calculators weren't necessary and in fact would have been slower.

1 comments

Yup. One clue you were going off course on a test in a high level math class was when all your numbers were getting rather crazy and unwieldy...

Usually the same rule applied in physics exams too...

Except some professors / PhDs deliberately set up exercise in a way that they involve large-ish (3-5 digits) or stupidly large (9+ digits) numbers to turn otherwise trivial exercises mostly into a mental math test. (Another all-time favourite of mine was the guy who always included an exercise in his exams that required you to determine the non-trivial prime factorization of a four digit number).

Good exam questions can be approached in multiple ways and are not a mental math test.

Bad math exam questions are usually those that can only be solved using one specific technique or lemma (ideally one that was only mentioned in passing once or twice) or require a lot of error-prone calculation.

One clue you were going off course on a test in a high level math class was when all your numbers were getting rather crazy and unwieldy...

We had one professor who was rather infamous for being really sloppy when writing exam questions. On more than one occasion did he accidentally transpose a couple of numbers in a problem, turning an equation that should have easily reduced to a trivial linear problem into a 4th degree polynomial with complex roots.