There's a handy command in Maple that produces a host of trigonometric identities - please see the help page for trigsubs. It'll save you hunting around Wikepedia ;-) Hope this helps. J. Tarr

There's a handy command in Maple that produces a host of trigonometric identities - please see the help page for trigsubs. It'll save you hunting around Wikepedia ;-) Hope this helps. J. Tarr

You might care to take a look at kronprod in Robert Israel's Maple Advisor Database. J. Tarr

Absolutely right - unless one is using that abomination the document mode. J. Tarr

Absolutely right - unless one is using that abomination the document mode. J. Tarr

Please see ?hyperlink,insert and links to related help pages. Hope this helps. J. Tarr

Having re-read the help page for the assume facility, I (re)discovered this gem:

Important: If the is command is used with a Maple type typename, it returns true if the corresponding type(..., typename) command returns true. This may lead to unexpected results. There are convenient tests that can be used when programming with variables that carry assumptions. To test if the expression is real, use is(Im(x)=0). To test whether x is real and positive, use is(signum(x)=1). To test whether x is an integer, use is(Im(x)=0) and is(frac(x)=0).

So, if one places an assumption on something, expect the unexpected when testing the assumption, or find a test that does not involve a type-name. J. Tarr

John, Please see ?type,complexcons and ?type,complex and try this: restart: assume(x::complexcons): type(x,complexcons); assume(x::complex); type(x,complexcons); type(x,complex); type(x,complex(name)); Plainly, x cannot be of type complexcons, but can be of type complex name. Hope this helps. J. Tarr

John, May I suggest that you spend a little time with the following help pages? They should explain to you the differences between Document mode, Worksheet mode, 2d Input and 1D input (also known as Maple input). worksheet,help,usingdocumentsandworksheets (yes, all one word!) and Maple Tutorial WS You can access the "Classic" worksheet by opening cwmaple.exe in the Maple 11 folder bin.win, or clicking on the icon if it's on your desktop. Hope this helps. J. Tarr

Many thanks for your very helpful guidance. J. Tarr

Many thanks for your very helpful guidance. J. Tarr

Before posting above, I should have tried the commands gmax and gmin from Robert Israel's Database Advisor. They can deal with the expression mentioned above: restart; Digits := 30; libname := "C:\\mystuff\\Advisor" , libname; # insert path g := sin(x) + sin(2*x) + sin(Pi*x); y_min := gmin(g,x=0..1000,'x_min'); x_min; y_max := gmax(g,x=0..40,'x_max'); x_max; However even these potent commands can have difficulties with identifying the location of the maximum or minimum. I used plot and and guesswork to narrow the interval to be examined, but would be most grateful if Robert Israel could give us some guidance on this aspect. J. Tarr

Before posting above, I should have tried the commands gmax and gmin from Robert Israel's Database Advisor. They can deal with the expression mentioned above: restart; Digits := 30; libname := "C:\\mystuff\\Advisor" , libname; # insert path g := sin(x) + sin(2*x) + sin(Pi*x); y_min := gmin(g,x=0..1000,'x_min'); x_min; y_max := gmax(g,x=0..40,'x_max'); x_max; However even these potent commands can have difficulties with identifying the location of the maximum or minimum. I used plot and and guesswork to narrow the interval to be examined, but would be most grateful if Robert Israel could give us some guidance on this aspect. J. Tarr

You are right, I was using worksheet mode with Maple input. Document mode is too eccentric, and this seems to be another example. J. Tarr

The code works for me without the space between "if" and "(". Perhaps you inadvertently made some other correction while changing the OP's code? J. Tarr