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Thread ID: 142110	2016-04-28 07:24:00	A mathematical conundrum..................	Billy T (70)	PC World Chat

Post ID	Timestamp	Content	User
1419696	2016-04-29 06:29:00	My father had 50m of wire netting and wanted to make a temporary rectangular sheep pen against a straight fence. I used calculus to get the dimensions for the largest possible pen... Or you could have just divided 50m by 3 to find out how long each side could be.... I liked maths in high school as well, one of my best subjects up until the 6th form when I lost interest in school work and paid more attention to the girls. I find though that unless you use it regularly the skill fades with time. I'm still ok with numbers but find myself heading to google for anything tricky (Why repeat work someone else has already done :)) Some of it is often useful though - a 3, 4, 5 triangle is still the easiest way to lay out a square corner for example.	dugimodo (138)
1419697	2016-04-29 07:12:00	...... up until the 6th form when I lost interest in school work and paid more attention to the girls. I find though that unless you use it regularly the skill fades with time. 'twas maths you were saying has to be used regularly I hope... :) I just wondered if the last sentence referred to maths or girls. ;) Ken	kenj (9738)
1419698	2016-04-29 07:28:00	One or both, give it time I'll let you know.	dugimodo (138)
1419699	2016-04-29 09:47:00	Or you could have just divided 50m by 3 to find out how long each side could be.... 3 sides of 16.7m gives an area of 278 sq-m - your off-the-cuff suggestion 2 sides of 12.5m and 1 of 25m gives an area of 312 sq-m - my calculus solution My solution gives 34 sq-m (12%) more area than yours (if I've done it right) I remember thinking (I was at school at the time) that if the pen stuck out from the fence just one metre (a long narrow pen) then the area would be only 48 sq-m. And if it was just one metre along the fence and 24.5 m sticking out into the field, then the area would be 24.5 sq-m Somewhere in between those extremes the area had to reach a maximum. Calculus tells us what dimensions gives the maximum	BBCmicro (15761)
1419700	2016-04-29 10:48:00	I enjoyed maths at school too. No-body told me then that girls weren't supposed to! I did the maths for the whole class... I suppose in hindsight the teacher knew:)	R.M. (561)
1419701	2016-04-29 14:40:00	My bad, I had the Idea a square was the solution from somewhere. I see your answer works out as exactly twice as wide as it is high, could be useful if I ever need to know that again :)	dugimodo (138)
1419702	2016-04-30 03:56:00	3 sides of 16.7m gives an area of 278 sq-m - your off-the-cuff suggestion 2 sides of 12.5m and 1 of 25m gives an area of 312 sq-m - my calculus solution My solution gives 34 sq-m (12%) more area than yours (if I've done it right) I remember thinking (I was at school at the time) that if the pen stuck out from the fence just one metre (a long narrow pen) then the area would be only 48 sq-m. And if it was just one metre along the fence and 24.5 m sticking out into the field, then the area would be 24.5 sq-m Somewhere in between those extremes the area had to reach a maximum. Calculus tells us what dimensions gives the maximum Using the first derisive to get max area, so need know the perimeter, and assign varibles for the area; use a bit of algebra then calculus to optimize/maximize area as calculated here. (www.analyzemath.com) But is it for a 3 sided wire fence or 4 sided? With one side along the fence/barrier? As for those Billy T magnetic values, some are so low (possibly negligible?) and so high, you think converting to log(10) values might be more useful, since it will scale vastly different results within the same order of magnitude - useful for graphing/trending. or at least use significant figures, which excludes the zero's. Or use some other kind of notation.	kahawai chaser (3545)
1419703	2016-05-02 05:17:00	derisive = derivative ???	Tony (4941)
1419704	2016-05-02 08:44:00	derisive = derivative ??? Yep. Thanks...	kahawai chaser (3545)
1419705	2016-05-02 11:08:00	Hmmm . . . . . . . . . . . The above experiences are all very interesting, and take me back to memories of my first few weeks in the third form at Grammar School . Mathematics was never my forte, my main strengths being in language, science, and biology, but I was in the mainstream at Grammar . The maths teacher addressed only the brightest and best mathematicians in the class and left the rest to struggle, then after two years of being ignored, the drop-outs were shuffled off to a 'no maths' stream and forgotten . Paradoxically, my career path required some pretty regular calculations, though nothing much more complex than a basic arithmetic, algebra, and a smidgin of geometry, so I have remained fairly basic on maths . Hopefully today's teachers actually help their struggling students! Cheers Billy 8-{)	Billy T (70)
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