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Thread ID: 29820	2003-02-04 01:16:00	OT: A question for skilled mathematicians, or am I just thick?	Billy T (70)	Press F1

Post ID	Timestamp	Content	User
118071	2003-02-04 01:59:00	the ^ is to the "power of" But has graham said when you have a "power of" that is a fraction then it becomes a square root. But i don't know what the computer uses to represent square root. In excel you type "sqrt"	roofus (483)
118072	2003-02-04 02:05:00	> I want to solve the following examples for f = > 350 kHz > > 3454f (0.753) =? .35^.753=.453611 .453611(3454)=1566.771 > 493f (0.753) =? .45611(493)=223.63 > 9.06/f (0.247) =? .35^.247=.7716 9.06/.7716 = 11.74 > 4.13/f (0.247) =? 4.13/.7716 = 5.3526 > > Obviously the decimal fraction is a power or factor > of some sort but I'm not even sure that description > is correct. I'm picking that a scientific calculator > is required for this and I have one right in front of > me now, but the problem is I can't drive the thing > apart from a few very basic functions. > > Any help will be gratefully accepted. > > Cheers > > Billy 8-{) Imagine emoticon for face full of hope > here:......... > > > Oh how I wish I'd paid more attention in > maths all those years ago :( :( >	roofus (483)
118073	2003-02-04 02:29:00	>> I want to solve the following examples for f = >> 350 kHz >> 3454f (0.753) =? >.35^.753=.453611 >.453611(3454)=1566.771 So to get the answer to this with a Casio fx-82TL scientific calculator (standard school issue) I did this: .35 then press the x button with the y superscript on it, directly under the Off button .753 = 0.453611 x 3454 = 1566.771 Easy peasy. :-) Now, what did you say it was for? :p Why is my reply in bold? I have no bold formatting tags.	Susan B (19)
118074	2003-02-04 02:39:00	EUREKA :O I did it, and with the scientific calculator too B-) Now I can grab previously mentioned smartypants daughter when she gets home from school and show her something mathematical I know that she doesn't ]:) Thank you Roofus; once again PF1 shows it's colours as the premier forum for questions on just about any topic. Cheers Billy 08-{) :D :D :D Never give up Horses Hoof. Next step up is the Horse's **se and before you know it you'll be a Horse's Head :|	Billy T (70)
118075	2003-02-04 02:48:00	You were a fraction too late Sis :x I just found my way around my Casio fx-82TL scientific calculator (snap) and produced the correct answer. The world can sleep easy tonight knowing that the sum total of knowledge in the universe has just been increased by ^ B-) Cheers Billy Bro O8-{) :D Like the halo? :8}	Billy T (70)
118076	2003-02-04 03:01:00	Try a bit more, just for fun and maybe ejermakation. The expression x^y is short for “x raised to the power of y”. The number y is also called an “index” (plural is indices, unlike plural of the index in your book, or the infamous consumer’s price index etc which are indexes). y can be any number, positive, negative or zero. (x^0 always equals 1, no matter what x is, and x^(-1) is the reciprocal of x (that is, 1/x). If y is not a whole number (say its fractional) this raises some very interesting questions. Ask Excel say to calculate say (-2)^(0.5) and it gives the Excel equivalent of “don’t be silly”. But you’re not being silly and this sort of thing actually (in addition to having two answers, not just one) actually plays a very interesting role in electrical circuitry. If you have something like 2^0.345 Excel etc will give you one answer whereas actually there may be quite a number of valid answers. This sort of stuff is all good clean fun. Fortran used x**y for x^y, currently Excel calculates x**y = x*(10^y) , whereas Visual Basic gives the Visual Basic equivalent of “don’t be silly” if you try x**y. Before modern computers and calculators, the only feasible way to calculate x^y (other than in the simplest cases) was by logarithms, which were concepts invented by Briggs and Napier about 1600 for this sort of thing as well as to make multiplication easier. Rather than look up logarithm tables for their calculations of x^y etc., some mathematicians such as Karl Gauss and Zacharias Dase used to memorise the tables, effectively carrying tables of logarithms around in their memory for instant calculation(I don’t know to how many decimal places). Multiplication was easy to them, Dase (lived about 1770) could multiply two 10 digit numbers in his head and give the correct answer within about 5 seconds. People generally didn't bother retaining this ability (apart from parlour tricks) after the advent of modern calculators, and of course computers. (a) none of the above came from Google or other search engine (b) anything more you want to know?	rugila (214)
118077	2003-02-04 03:27:00	There have been some great brains out there alright rugila. Apart from the odd idiot-savant with narrowly focussed powers, there have been some quite normal individuals with fantastic mathematical powers. I seem to remember there was an Indian? gentleman around in recent times who could beat a computer to some answers, but even if not that fast, he could match a computer for accuracy and was probably more accurate than a pentium with the floating point error. Then there was me :( Cheers Billy 8-{) :| I think I'll go and have a lie down	Billy T (70)
118078	2003-02-04 03:37:00	Cheer up Billy, My daughter is doing a Uni maths paper (summer school, another week to go). I made the mistake of peering over her shoulder last night as she was working on a number of problems. Vaguely recognised the bracket things she was working with as a dim, dark distant memory but hadn't a clue what they were for - 2 numbers side by side, another pair below them and big brackets around all four. ??? I thought (briefly) about asking but figured the answer would probably require an asprin or two so departed rapidly. At least I can still beat her at scrabble!	Heather P (163)
118079	2003-02-04 03:44:00	That's matrix stuff, Heather. Very clever. I have programmed some of this (simple only) for graphics transfomations, once upon a time. I've forgotten it all. :D	Graham L (2)
118080	2003-02-04 03:56:00	Matrix. That also rings a very distant bell but I still can't remember what they were for. Actually, maths was my best subject at school but it's the old story of "Use it or Lose it". My mathematical streak has turned into more of a logic streak. Complex formulaes these days start headaches so I try to avoid them. Logical processes on the other hand... <* sets off to sort a pile of papers into a logical order in order to make sense of a problem /*>	Heather P (163)
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