Timeline for Should I avoid writing: $ 11:40 - 15 \text{ min} = 11:25$, and what are alternatives to this way of writing?
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Apr 13, 2021 at 2:58 | comment | added | Daniel R. Collins | Another example in this class: Pointer arithmetic in C/C++ (i.e., arithmetic on addresses in memory). In this case, the operational limitations you describe are strictly enforced by the language standard and compilers. | |
| Apr 12, 2021 at 17:42 | comment | added | Chris Cunningham | I was able to find the essay referenced in the above comments here archive.org/stream/Surely-youre-joking-mr.-feynman/… | |
| Apr 12, 2021 at 17:25 | comment | added | Rusty Core | (3) But, this is exactly what authors of the textbooks that Richard Feynman once reviewed, did: "Red stars have a temperature of four thousand degrees, yellow stars have a temperature of five thousand degrees, etc ... John and his father go out to look at the stars. John sees two blue stars and a red star. His father sees a green star, a violet star, and two yellow stars. What is the total temperature of the stars seen by John and his father?" and I would explode in horror. It was awful! All it was was a game to get you to add, and they didn't understand what they were talking about. | |
| Apr 12, 2021 at 17:24 | comment | added | Rusty Core | (2) So, I have no problems adding 1999 to 2021: both "measurements" are the intervals from the 0 year, so the result will be the interval from the 0 year. Likewise, I have no problem with 22 years - 2021 year, it will be a B.C. date, so what? Temperature is conceptually different, it is a physical property, and temperatures of the objects cannot be added. This cannot be explained with math alone. | |
| Apr 12, 2021 at 17:18 | comment | added | Rusty Core | (1) Thanks for reminding how the number line is introduced, and how numbers are added or subtracted using the number line: using a pair of compasses you open it to the size of the unit segment, and then make as many equal segments on the number line as the first addend. Then you do the same with the second addend. The tick you marked is the answer. Is it a "measurement" or an interval? I think, both. Absolute value of an integer is the distance from zero. And you can do it in any order, illustrating commutativity of addition. And you can have more than two addends, illustrating associativity. | |
| Apr 12, 2021 at 15:30 | history | answered | Chris Cunningham | CC BY-SA 4.0 |