Wikipedia:Reference desk/Archives/Mathematics/2007 February 19

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[edit] February 19

[edit] Best calculus textbook

I've heard very often of Tom Apostle's Calculus I and Calculus II written in the 40s and 50s, which are very proof-heavy, well, entirely proof-based. What are your opinions on the best calculus textbooks? [Mαc Δαvιs] X (How's my driving?) ❖ 08:28, 19 February 2007 (UTC)

I can also recomend Leithold's book. Specially for beginners it is a good choice. Mr.K. (talk) 13:48, 19 February 2007 (UTC)
More information about your expectations would help. Do you want a graphic-rich easy introduction? Well-grounded proofs? Higher mathematics insight? Emphasis on engineering/physics applications? A modern revision? One of the non-standard analysis presentations?
Most texts I've seen do not impress me. Richard Courant and Fritz John do. Try a variety of books online, including those listed by Stef and at AMS. --KSmrqT 04:27, 20 February 2007 (UTC)

[edit] simplex method

using this tool:

http://people.hofstra.edu/faculty/Stefan_Waner/RealWorld/simplex.html

I've entered in and solved:

Maximize p = 3x+y+3z subject to

  • 2x+y+z <= 2
  • x+2y+3z<=5
  • 2x+2y+z<=6

I follow up to Tableau 2 but what doesn't make sense is in Tableau 3, column s1 and the last row. Shouldn't this number be negative from the column s1 row 2? —Preceding unsigned comment added by 75.8.72.171 (talk • contribs) 08:46, 2007 February 19

The given value of 1.2 is correct. This has come from a pivot on the (s2,z) element in Tableau 2, which has value 2.5; to eliminate z from the objective row (current element -1.5), 60% of the 2nd (s2) row is added to it. 60% of -0.5 added to 1.5 gives 1.2, as displayed. Someone will tell you to sign your post, can't say it bothers me.—86.132.165.26 10:25, 19 February 2007 (UTC)
(Constraints formatted, unsigned signed.) Wikipedia asks for the signature, on all talk pages; individuals like me merely remind. If you're curious why, you could read Wikipedia:Signatures. It says
  • Signing your posts on talk pages and other Wikipedia discourse (but not on articles) is not only good etiquette; it also facilitates discussion by helping other users to identify the author of a particular comment, to navigate talk pages, and to address specific comments to the relevant user(s), among other things.
Coherent conversations are easier when we know who said what. (And Oleg Alexandrov would add, please remember to use the edit summary box.) --KSmrqT 12:23, 19 February 2007 (UTC)
It's also good etiquette for the original poster to acknowledge an answer to the problem posed. —86.132.236.24 14:26, 20 February 2007 (UTC)
We don't ask for thanks, but we do appreciate it. Also note that indenting responses is standard practice; accidentally disrupting others' posts is not (both fixed). :-) --KSmrqT 14:42, 20 February 2007 (UTC)

[edit] Math Formatting Help

If possible, could someone give me the wiki formatting for the equation F=6.6742x10^-11N*m^2/kg^2(200g*1kg)/(10cm*0.01m/cm)^2 ?

F= \frac{6.6742\times10^{-11}\ \mbox{N} \ \mbox{m}^2 \ \mbox{kg}^{-2} \, (200 \ \mbox{g} \times 1 \ \mbox{kg})} {(10 \ \mbox{cm} \times0.01 \ \mbox{m})^2}

Is this what you wanted? Hope I helped. Deltacom1515 03:51, 20 February 2007 (UTC)

Read up on LaTeX :) 213.48.15.234 09:57, 20 February 2007 (UTC)
WP:MATH will provide all the answers. --h2g2bob 14:11, 20 February 2007 (UTC)