when I eval an expression at one x value it works but why does eval fail to work when multiple values of x are passed on to eval as a list....

a:=x^2

eval(a,x=9) will result in 81.

But eval(a,x=[9,10]) does not produce   81,100 .

I was under the impression that multiple values of x can be passed on as a list. Please let me know where I am making mistake(s). Thanks in advance !!

I am thinking about using Maple for my math calculations and work. Is Maple going to be around and vibrant since its acquisition by a Japanese software group? Just wanted to make sure I am not investing time and resources in a technology that might be phased out. Thanks in advance!

I need help with unapply command in order to create functions out of solutions produced by the solve command. For example, I want to solve ax^2+bx+c=0 and create a function out of the first of the two results. Thanks in advance!!

How can I use the eval command to evaluate x^2 at  [5,7]. I know how to eval x^2 at just x=5 or just x=7 but I am not sure how to evaluate the entire list [5,7]. Thanks in advance !!

what is the purpose behind the command gc()  ? Thanks in advance !!