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odd mathematica blindspot


hey all,

I was wondering why the following didn't output any solutions. I'd think 
it would be easy:

	Solve[(999999999999/10000000000000)^x == .5, x]

It gives no solutions. What's really odd is when you say:

	Solve[(999/1000)^x==.5, x]

which *does* give solutions, in the form:

	{{x -> 692.801... }}

Also, just curious, but how do you extract 'x' from the above? 
Say I wanted to plug the above solution into another equation.. 
In perl I'd say something like:

y = Solve[(999/1000)^x == .5, x];

3 * y->{x}  # replaces with 692.81

etc. etc.

but this doesn't seem to work. How do you access parts of a mathematica
datastructure/hash?

And finally, how do you set values with the tty? ie: suppose my backspace and
delete key aren't working with math.exe (they aren't) and I want them to
delete typos. In unix this would be stty erase ^H. In mathematica...?

Thanks much for any help,

Ed


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