With my calculator, I can store and then use intermediate results in the following way. Lets say the result of an equation is 1.234 and I will be using those results in other calculations. If I enter 1.234->a where the arrow represents the store key, the value of 1.234 in now stored as "a" and I can use "a" in further calculations, for example 2a followed by enter will return 2.468. How do I do the same type of thing with maple? (Thank you)

With my graphing calculator (TI-voyage200) I can expand and collect multiple angles per the familiar trig foumulas. For example with my calculator I can enter tExpand(sin(2*x)) and 2*sin(x)*cos(x) is returned. To do the reverse I simply enter tCollect(2*sin(x)*cos(x)) and sin(2*x) is returned by my calculator. With Maple, I find that I can use expand(sin(2*x)) to get 2*sin(x)*cos(x) but collect(2*sin(x)*cos(x)) doesn't perform the reverse the operaton. How can I do the reverse operation, for instance by entering what command along with 2*sin(x)*cos(x) and have sin(2*x) returned???

In the Maple 11 user manual, at the beginning, on page 1 is an integral of sin(1/x)dx from zero to pi. The solution is given as an expression including -Ci(1/Pi). No definition or explanation is given for Ci. So my obvious question is what in the world is this Ci? I suspect it is a constant but if that is true, why doesn't the program present it's value? Then on page 20 is another integral where the answer is given as 1/2 erf(1)sqrt(pi). Here again, there is no explanation of what in the world erf(1) means, so what in the world is erf(1)?

In reading through the Maple 11 "Getting Started Guide," on page 81 is paragraph 4.2, which is titled "Top Commands," the booklet lists and describes a number of commands such as plot, solve, fsolve, eval, etc., with out any comment. What is the significance of these commands among the many, and what is meant by "top" commands. Is there a hierarchy of commands? Or do they mean these are the most used or what? I don't understand what I am missing here or why this list of commands in included. Again, there is no discussion, just the table of commands.

I read and re-read the manual on using spell check but can not get it to work. For example, I open maple to a fresh worksheet, and at the prompt type in now is the qoittja. Then I go to tools and select spell chek. Instantly I get a small popup message that says spell check complete but it didn't find the obvious mistake (quoittja is not a word). What in the world is going on here? How do I use spell check? Could you offer an example please? Thanks.