Smallest positive numerical solution of an equation in one variable

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I have some functions, all of which are functions of variable $x$ but some of them may not have any positive solutions. It is known that at least one of them have a positive solution. Now I need a list of all smallest positive solutions for those functions. For example consider $f=x^2+3x+2$ and $g=2^{(5x + 1)} - 3.2^{(3x + 1)}$. Here $f$ doesn't have any positive root but $g$ has (0.792481250360578). I want a sage code like min(solve([f,x>1],x))+min(solve([g,x>1],x)) to get the list as [0.792481250360578]. Thank you in advance.