Talk:Heron's formula

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how does making a>b>c change the formula? i can't see how it influences it.

It changes the stability of the numerical compuation on a floating-point processor. In the limit case of needle triangles, where one side is very small, you want that side to be 'c' in the formula. In perfect real-number computation it doesn't make any difference, of course, but if you're not worried about numerical stability, you wouldn't use this version of the formula anyway; you'd just use the millenia-old original one. --Delirium 05:51, 9 November 2005 (UTC)
It would seem to be the unique parenthesization minimizing the intermediate results while keeping them all nonnegative, subject of course to the triangle inequality. As such it never uses addition when subtraction is possible. However I'd be interested to see an example where (a+b)+c is less accurate than a+(b+c). --Vaughan Pratt (talk) 20:42, 22 February 2008 (UTC)

When did Heron, otherwise known as Hero discover the fomula?

The article says in the 1st century A.D. Do you need a date? --Gesslein 14:22, 25 July 2006 (UTC)

It would be nice but my homework is due in tomorow so you prob. won't tell me in time. I'm sure 1st Century AD is enough (hopefully). :D Jess

I don't have a date, probably sometime near 50 A.D. it was published. --Gesslein 19:13, 28 July 2006 (UTC)

The section "Ch'in Chiu-shao's fomula" really belongs to the history section. Most of it doesn't add to Heron's formula and can be found on Ch'in Chiu-shao’s. The sentence "This fomula was proved recently by Wu Wenjun" is very strange! Anyone can say were did it came from? Anyway I am deleting this section and making the appropriate changes. Ricardo sandoval 05:19, 9 July 2007 (UTC)

[edit] Spelling

is another name for this formula Hero's Formula? —Preceding unsigned comment added by 63.215.27.161 (talk) 00:57, 27 November 2007 (UTC)

Yes, Hero's Formula and Heron's Formula are the same. The spellings "Hero of Alexandria" and "Heron of Alexandria" are both used, and neither is correct, although the Greek language purists would probably prefer the version with the n. --♦IanMacM♦ (talk to me) 08:11, 27 November 2007 (UTC)

[edit] Error

There is an error in the expression that follows "Expressing Heron's formula with a determinant in terms of the squares of the distances between the three given vertices,". It is missing a necessary minus sign in front of the determinant and under the square root radical. See http://mathworld.wolfram.com/HeronsFormula.html —Preceding unsigned comment added by BillFish321 (talk • contribs) 09:20, 6 March 2008 (UTC)