Wikipedia:Reference desk/Archives/Mathematics/2007 May 1

= May 1 =

Latus Rectum
Is anyone aware of the actual translation of "Latus Rectum"? Just out of interest....Wbchilds 06:41, 1 May 2007 (UTC)


 * i believe it is "right line" 124.189.99.48 07:33, 1 May 2007 (UTC)


 * Latus, later-is means "side", and rect-us, -a, -um means "straight", so together the literal meaning of latus rectum is "straight side". --Lambiam Talk  10:22, 1 May 2007 (UTC)


 * The Romans were accomplished engineers, but the Greeks before them directly contributed more to our mathematics vocabulary. However, Latin — or something resembling it — became a common language for European publication long after the fall of the Roman empire, so many terms entered our vocabulary in that way. For example, Isaac Newton was born 1642 (depending on calendar) in England, but his most famous work is Philosophiae Naturalis Principia Mathematica; and Carl Friedrich Gauß was born 1777 in (what is now) Germany, and went on to write Disquisitiones Arithmeticae. Even William Rowan Hamilton (born 1805), who wrote in English, gave us Latin-based terms like vector and scalar. --KSmrqT 17:54, 1 May 2007 (UTC)

Fun With Mathese
I heard this somewhere else, "When you ask your friend to define a Bajillion, he responds with 1 followed by a bajillion zeroes and then you set up the logarithm and figure out that a bajillion is actually a fairly small complex number." It was a comment on a math forum. I offered the following response: "Given that...x = 10^x, where x is a bajillion, x = omega would solve the equation nicely and give a more intuitive result. In roughly decimal format, that would be a sequence of a_n where a = 0 for any natural number n, and a = 1 for n = omega." I based it on the Ordinal Arithmetic article. Is it right? Black Carrot 22:30, 1 May 2007 (UTC)


 * In the domain of ordinal numbers, indeed 10ω = ω, but the last assertion about decimal formats mixes domains in a meaningless way. The system of decimal notation (or, in general, positional notation) of numbers only applies to "ordinary" numbers. Although, perhaps, the definitions could be extended to the domain of ordinal numbers, such an extension would have to be defined before the last assertion could become meaningful. There is no obvious and direct extension, one crucial issue being that in ordinal arithmetic addition and multiplication of ordinals are both not commutative, and multiplication on the right does not distribute over addition. --Lambiam Talk  06:07, 2 May 2007 (UTC)


 * That's a good point. Black Carrot 08:23, 2 May 2007 (UTC)