Solve problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg97989] Solve problem*From*: araldocampanini at gmail.com*Date*: Fri, 27 Mar 2009 05:35:47 -0500 (EST)

I have a Solve[...] which gives me solutions like {{b1 -> -2, a1 -> -1 }, {b1 -> 0.5, a1 -> 3}} or like {{a1 -> 1, b1 -> 3}} How can I get the positive value for a1, which is 3 in the first case and 1 in the second one? Bruno