check out ?convertsys

M:=Matrix(3,3,fill=1);M[1,1]:=1e-5;M;
map(fnormal,M,3);

check used commands in related help pages, also consider datatypes if necessary (mixed floats/integers are bad sometimes)

maybe like this?

c:=(N,m)->1/(N^m*m!)*D[1$m](f)(t);

Type cntrl+shift+r

If I follow the menu Edit->Execute->Worksheet, then I see Cntrl+shift+enter as keyboard shortcut to execute the whole worksheet. 

Hi,

better use Multibody->Joints and Motions->Prismatic Component

Do you mean the view for a multibody model? At the bottom left of the center screen in the 3D animation view, there is a gear wheel symbol that lets you switch between playback mode and assembly mode.

see ?2dmathshortcutkeys and look for overscript

see ?convertsys

++++++ some chars to meet the 15 character lower limit for answers. 

You can specify sin, cos etc. in the variable list:

solve([tan(x)+y*sin(x) = 1, tan(x)-y*sin(x) = 0], [tan(x), sin(x)]);

[[tan(x) = 1/2, sin(x) = 1/(2*y)]]

hard to tell without seeing you circuit, but there is a working example in MapleSim under Examples/Electrical/DiodeBridgeRectifier. You can take it as reference. Typical mistake: do you have a ground component in your circuit?

int(sin(x)*Dirac(x-zeta), x = 0 .. l) assuming zeta > 0, l > zeta;

Hi, you can define local variables i.e. 
local gamma;

see ?physics,examples

see left tabs

Project->Stored results

click "rename this result to save it"

now check inspector tab (on the right side of the screen) and click export icon

the problem is auto-simplification that cannot be suppressed easily. There is no switch for it, only funny workarounds. At least in Maple 17.