Problems with Derivative, Piecewise, Assuming
- To: mathgroup at smc.vnet.net
- Subject: [mg55898] Problems with Derivative, Piecewise, Assuming
- From: Enrique Zeleny <ezeleny at fcfm.buap.mx>
- Date: Sat, 9 Apr 2005 03:55:49 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Evaluate each one of the following inputs (the derivative isnt defined in
any point)
D[Log[-Abs[Sin[x]]], x]
D[Piecewise[{{Log[Sin[x]], Sin[x] < 0}, {Log[-Sin[x]], Sin[x] > 0}}], x]
Assuming[x \[Element] Reals, D[Log[-Abs[Sin[x]]], x]]
Assuming[x \[Element] Complexes, D[Log[-Abs[Sin[x]]], x]]
Assuming[x \[Element] Reals, D[Piecewise[{{Log[Sin[x]], Sin[x] < 0},
{Log[-Sin[x]], Sin[x] > 0}}], x]]
Assuming[Sin[x] > 1 && x \[Element] \[DoubleStruckCapitalR],
D[Piecewise[{{Log[Sin[x]], Sin[x] < 0}, {Log[-Sin[x]], Sin[x] > 0}}],
x]]
Future work for Mathematica developers
Thanks