Solve without vars
- To: mathgroup at smc.vnet.net
- Subject: [mg130347] Solve without vars
- From: juchheissassa at gmail.com
- Date: Wed, 3 Apr 2013 22:53:18 -0400 (EDT)
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- Delivered-to: l-mathgroup@wolfram.com
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I happened to hit on the following curious thing:
If I use Solve with {} instead of vars, I actually get a solution.
Is this documented anywhere? What are the rules?
e.g.:
Solve[a x + y == 7 && b x - y == 1, {}] yields {{y -> 7 - a x, b -> (8 - a x)/x}}
while
Solve[a x + y == 7 && b x - y == 1, {x,y}] yields {{x -> 8/(a + b), y -> -((a - 7 b)/(a + b))}}