Re: Examples using Trig option
- To: mathgroup at smc.vnet.net
- Subject: [mg35274] Re: [mg35237] Examples using Trig option
- From: BobHanlon at aol.com
- Date: Fri, 5 Jul 2002 02:21:48 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
In a message dated 7/3/02 7:18:56 AM, ErsekTR at navair.navy.mil writes:
>The usage message for Trig says:
>
>Trig is an option for algebraic manipulation functions which specifies
>whether trigonometric functions should be treated as rational functions
>of
>exponentials.
>---------
>
>The built-in functions that have the Trig option are:
>Apart, ApartSquareFree, Cancel, Coefficient, CoefficientList, Collect,
>Denominator, Expand, ExpandAll, ExpandDenominator, ExpandNumerator,
>Exponent, Factor, FactorList, FactorSquareFree, FactorSquareFreeList,
>FactorTerms, FactorTermsList, FullSimplify, Numerator, PolynomialGCD,
>PolynomialLCM, PolynomialMod, Resultant, Simplify, Together.
>
>
>After searching all available documentation I can't find a single example
>of
>where
>f[expr, Trig->True] would give a different result than
>f[expr, Trig->False], and I can't come up with one on my own. Can you give
>some examples. An example for each function above is not necessary.
expr=Sin[x+y]-Cos[x-y];
Apart[expr, Trig->#]& /@ {True, False}
{-Cos[y] (Cos[x]-Sin[x])+(Cos[x]-Sin[x]) Sin[y],-Cos[x-y]+Sin[x+y]}
Expand[expr, Trig->#]& /@ {True, False}
{-Cos[x] Cos[y]+Cos[y] Sin[x]+Cos[x] Sin[y]-Sin[x] Sin[y],-Cos[x-y]+Sin[x+y]}
Factor[expr, Trig->#]& /@ {True, False}
{-(Cos[x]-Sin[x]) (Cos[y]-Sin[y]),-Cos[x-y]+Sin[x+y]}
Bob Hanlon
Chantilly, VA USA