Re: Factor, Expand. Daytime Hours.
- To: mathgroup at smc.vnet.net
- Subject: [mg32315] Re: Factor, Expand. Daytime Hours.
- From: "Allan Hayes" <hay at haystack.demon.co.uk>
- Date: Sat, 12 Jan 2002 21:32:33 -0500 (EST)
- References: <a1p2gh$6vq$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Mathtias, For your facorisation problem: Factor[a^2+b^2, Extension->{I}] (a- I b) (a+ I b) -- Allan --------------------- Allan Hayes Mathematica Training and Consulting Leicester UK www.haystack.demon.co.uk hay at haystack.demon.co.uk Voice: +44 (0)116 271 4198 Fax: +44 (0)870 164 0565 <Matthias.Bode at oppenheim.de> wrote in message news:a1p2gh$6vq$1 at smc.vnet.net... > Dear Colleagues, > > once again I am doing maths with my son and in doing so we look for more > solutions to the textbook problems after having solved them using our > built-in biochemical processors. > > So: > 1. > Factor[a^2 - b^2] yields - predictably - > > (a - b)*(a + b). > > The question "what yields the factorization of a^2 + b^2" is not > far-fetched. > > How can I coax MATHEMATICA into giving: (a - I*b)*(a + I*b)? > Are there more "simple" solutions of the same structure (... - ...)*(... + > ...) or some wizardry like (... + or - ...)^t, where t is some composite > expression ? > > 2. > Where can I find the function that gives the daytime hours between sunrise > and sunset as a function of date and latitude? > > Thank you for your help. > > Best regards, > > Matthias Bode > Sal. Oppenheim jr. & Cie. KGaA > Koenigsberger Strasse 29 > D-60487 Frankfurt am Main > GERMANY > Tel.: +49(0)69 71 34 53 80 > Mobile: +49(0)172 6 74 95 77 > Fax: +49(0)69 71 34 95 380 > E-mail: matthias.bode at oppenheim.de > Internet: http://www.oppenheim.de > >