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BS: Matha questions (Math?)
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Subject: Maths questions From: Red Eye Date: 29 Apr 02 - 11:37 AM y with a little 3 over the top = 21 952 Answers please with explanation Thanks |
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Subject: RE: Matha questions From: gnu Date: 29 Apr 02 - 11:48 AM 28X28X28 |
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Subject: RE: Matha questions From: Red Eye Date: 29 Apr 02 - 12:11 PM X2 + 5x = 414 ? |
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Subject: RE: Matha questions From: Sorcha Date: 29 Apr 02 - 12:16 PM I think Red wants to know HOW you get there...... |
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Subject: RE: Matha questions From: SINSULL Date: 29 Apr 02 - 12:20 PM "y" cubed meaning y X y X y = 21952. gnu's got it. y = 28. |
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Subject: RE: Matha questions From: Sorcha Date: 29 Apr 02 - 12:22 PM Yes, but just how did you solve for y? |
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Subject: RE: Matha questions From: Red Eye Date: 29 Apr 02 - 12:26 PM Yes please? |
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Subject: RE: Matha questions From: Wincing Devil Date: 29 Apr 02 - 01:23 PM Take the Cube root of 21952 |
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Subject: RE: Matha questions From: Wincing Devil Date: 29 Apr 02 - 01:38 PM OOPS: Forgot the algorithm. Here's the algorithm, in perl and Basic, (basically, raise the number to the 1/3 power):
#Perl 'BASIC
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Subject: RE: Matha questions From: Pene Azul Date: 29 Apr 02 - 01:49 PM x2 + 5x = 414 x2 + 5x - 414 = 0 (x + 23)(x - 18) = 0 x + 23 = 0 or x - 18 = 0 x = -23 or x = 18 |
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Subject: RE: Matha questions From: catspaw49 Date: 29 Apr 02 - 01:50 PM If you had a cube root, wouldn't it be really tough on your sex partner? Square peg, round hole.........all that sort of thing........ Spaw |
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Subject: RE: Matha questions From: Joe Offer Date: 29 Apr 02 - 01:50 PM I added "BS:" to the title of this thread because it doesn't have anything to do with music (I think). After we finish "matha" questions, do we go on to "fatha" questions? -Joe Offer, confused- |
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Subject: RE: BS: Matha questions (Math?) From: Wincing Devil Date: 29 Apr 02 - 01:56 PM Good Idea, Joe, to add BS to the thread title! Because math is pure, unadulterated BS (Boring Stuff). Music is, on the other hand, also BS, but in this case, Beautiful Stuff. To bad the two are so inseperably intertwined. |
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Subject: RE: BS: Matha questions (Math?) From: Hilary Date: 29 Apr 02 - 05:52 PM I used to love doing quadratic equations ( like Red-eye's question), squaring the circle, non-homogeneous something-or-others-that-I-can't-remember ,and of course - calculus. Unlike in real life - you know there is a specific right answer to be working towards. (or 2 answers for quadratics) Hilary |
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Subject: RE: BS: Matha questions (Math?) From: McGrath of Harlow Date: 29 Apr 02 - 06:46 PM I remember it was quite fun working out those quadratic and simultaneous equations. Puzzles. But I never got to the stage where I ever found out what they were for.
Then when it got to my son bringing home Maths homework, I found they seemed to have completely junked all the stuff I'd done, and brought in a whole competely different set of puzzles. And my son never got to understand what it was all for either. |
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Subject: RE: BS: Matha questions (Math?) From: Bert Date: 29 Apr 02 - 10:59 PM Math is for fun. It's all a game. It all started when folks asked what would happen if they separated number from quantity. Of course you can't do it really so you just pretend you can, so it's really all a game of let's pretend. The secret is not to take it too seriously. It just so happens that some of it turns out to be quite useful. Quadratic equations come in useful if you're designing suspension bridges which by a happy coincidence are parabolic in shape. Simultaneous equations crop up in many activities in real life from theory of structures to electronics. Their study led to another branch of Math called determinants which in turn led to matrices. Matrices are useful when doing transfomations in 3 Dimensional geometry so they are used for CAD as well as for guidance in the space industry. |
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Subject: RE: BS: Matha questions (Math?) From: GUEST,Hilary, not logged in Date: 30 Apr 02 - 02:36 AM ...ah yes, matrices - great fun Dividing one matrix by another isn't 'allowed' - but you can multiply by an inverse. but Hamiltonians - yukk. Hilary |
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Subject: RE: BS: Matha questions (Math?) From: GUEST,Pavane Date: 30 Apr 02 - 07:42 AM Sorry. Suspension bridges are only parabolic if their weight is zero! Not very likely in the real world. Their real shape would be a Catenary curve first described about 1690. Of course, Music is heavily based on maths, for example the relationships between semitones in the even-tempered scale is based on the 12th root of 2. A perfect 5th has a frequency ratio of 3:2,i.e. 1.5, but an even tempered 5th is VERY slightly flatter, being the (12th root of 2) to the power of 7. Easy to work out on your calculator.
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Subject: RE: BS: Matha questions (Math?) From: Ringer Date: 30 Apr 02 - 09:28 AM Hilary: I think completing the square, not squaring the circle! |
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Subject: RE: BS: Matha questions (Math?) From: Louie Roy Date: 30 Apr 02 - 09:50 AM Music and math are very much related.They are both fun and challenging and the harder you work on each one the more knowledgable you will be.Both of them tax your mind.I enjoy seeing these math questions pop up occassionally for all at once you have to put on your thinking cap.Oh yes you can square a circle I have the formula,but I don't have enough smarts to complete the complicated instructions.Anyone like to try?Louie Roy |
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Subject: RE: BS: Matha questions (Math?) From: GUEST Date: 30 Apr 02 - 11:25 AM It is geometrically impossible to "square a circle" using the time-honored classical implements ( straightedge and compasses. ) It is, however, absurdly easy to construct a square with an area which approximates that of any given circle, to as close a tolerance as necessary.
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Subject: RE: BS: Matha questions (Math?) From: GUEST,Hilary, not logged in Date: 30 Apr 02 - 01:42 PM Hi Ringer/guest - you're right, I'm afraid squaring the circle was what one student enjoyed calling it - & the name has stuck in my memory much more than the technique. It was a VERY long time ago ! (& I wasn't a very attentive student) I can remember being in the lecture room - but that's about it,did it involve adding a constant to both sides of the equation ????? It crossed my mind to look it up, but most of my text books were stolen. Thank for reminding me. Hilary |
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Subject: RE: BS: Matha questions (Math?) From: Joe_F Date: 30 Apr 02 - 06:52 PM Guest,Pavane: You are mistaken. A cable supporting only itself has the form of a catenary. If it is supporting a bridge, and if (as is usual) the bridge has uniform weight per unit of *horizontal* distance, and it weighs much more than the cable, then the cable is (very nearly) parabolic. Turn the problem upside down, and you have a parabolic *arch* supporting the road. That is, it *should* be parabolic in order for it to be under pure compression, as the cable was under pure tension. Make it any other shape, and it will not be happy. |
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Subject: RE: BS: Matha questions (Math?) From: Bert Date: 30 Apr 02 - 09:07 PM Ah yes Hilary, Hamiltonian Quaternians! Also used in CAD programming. Back in the days when every byte was precious they saved a lot of file space. You'll still find them in MicroStation DGN files. And Joe F, you're right of course, it's the weight of the road that makes suspension bridges parabolic enough to use quadratic equations to solve for the forces in the cables. A catenary would be much more awkward to solve. |
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Subject: RE: BS: Matha questions (Math?) From: Hrothgar Date: 01 May 02 - 04:05 AM ..and how can we use trigonometry in music, so that we can really enjoy it? |
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Subject: RE: BS: Matha questions (Math?) From: Nigel Parsons Date: 01 May 02 - 05:15 AM Hrothgar: "and how can we use trigonometry in music, so that we can really enjoy it? " Simple, ask any Triangle player, or: Go square dancing, or: Anything that takes you to your musical roots |
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Subject: RE: BS: Matha questions (Math?) From: Bert Date: 01 May 02 - 05:47 AM Unfortunately the math involved with music doesn't really help us enjoy it any more. Pythagoras discovered that if you stop a string to half it's length it will sound it's octave, and if you stop it to a third of it's length it will sound a fifth. But we usually use the equally tempered scale which is slightly different. It is a convenient piece of mechanical jiggery pokery that allows us to play in different keys on the same instrument.The mathematics is fairly simple. Again if you stop the string to half it's length you will get the octave. But this time instead of dividing the string into it's natural musical divisions we divide it in such a manner that the ratio between the lengths of one fret and the next is the same. Now by didving the string into twelve steps this way we need to look for a number which multiplied by itself twelve times will give twice the length. The number that does this is the twelfth root of two. Now the fifth is about 1.33484 which is just a little over a third. This is what makes some notes and chords sound a little off. |
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Subject: RE: BS: Matha questions (Math?) From: GUEST Date: 02 May 02 - 12:34 AM In a MUSIC FORUM?
Because its the MUDCAT MAGAZINE and CHAT |
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Subject: RE: BS: Matha questions (Math?) From: GUEST,macca Date: 02 May 02 - 02:52 AM Check out Tom Lehrer's "New Math" with those magnificent lines... "It's so simple, so very simple.. That only a child can do it." Know how you feel, McGrath of Harlow.... and I HAVE to use at least some math in the fantasy world they call real life |
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Subject: RE: BS: Matha questions (Math?) From: Mark Cohen Date: 02 May 02 - 03:04 AM Joe F, so it would seem those circular arches under the Roman aqueducts have been unhappy for a very long time....maybe they need some hydrotherapy. :-) Aloha, Mark |
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Subject: RE: BS: Matha questions (Math?) From: Joe_F Date: 02 May 02 - 07:17 PM Mark: I believe they are overbuilt (weight comparable to, if not greater than, that of what they support). Thus, their shape probably doesn't matter a lot. I can think of three songs that mention triangles: "Grand Canal", "Lobachevsky", & "The Shape of Things". Oh, yes, and then there's that major general who has a lot o' news about the square of the hypotenuse. None, however, gives enough information to apply trigonometry. |
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Subject: RE: BS: Matha questions (Math?) From: Bert Date: 02 May 02 - 08:21 PM Voussoir arches were circular back in Roman times, since then, other shapes have been used. The pointed arch was invented so that church vaulting arches of different spans could meet at the top. This avoided the complex (in stone at least) intersections of circular arches. Later, for aesthetic reasons, cycloidal and elliptical arches were used. Brunel build a notorious elliptical arch at Maidstone which many people thought would fail. It is still carrying rail traffic to this day. Parabolic arches really only came into their own since the introduction of reinforced concrete. As a side issue, the arches used by the Marsh Arabs to construct their Mosques of rushes, appear to be either parabolic or elliptical. And GUEST, if you care to read the thread in it's entirety instead of going off half cocked you will find some musiacl references. |
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Subject: RE: BS: Matha questions (Math?) From: GUEST,Pavane Date: 03 May 02 - 02:07 AM I wouldn't like MY fifths to have a ratio of 1.33484. I think about 1.49 would be more like it. Perhaps you only took the 5th power, not the 7th? If you really want some trig, remember that all musical notes can be built up from Sine waves of the fundamental and its harmonics. This affects the design of instruments. For example, conical and cylindrical pipes have different proportions of the various overtones, and therefore sound different. Closed and open-ended pipes also perform differently.
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Subject: RE: BS: Matha questions (Math?) From: Hrothgar Date: 03 May 02 - 06:39 PM I just realised that triggernometry fits into songs like "Frankie and Johnnie." |