[sage-devel] Re: solve an algebraic expression

2011-05-16 Thread kcrisman
On May 15, 7:28 pm, rjf wrote: > squaring both sides of an equation often produces extraneous > "solutions" as you've illustrated. > Maxima's solve program produces the illustrated form when it cannot > solve any better. It is presumably a feature. > > Also a feature:  It does not produce extran

[sage-devel] Re: solve an algebraic expression

2011-05-15 Thread rjf
squaring both sides of an equation often produces extraneous "solutions" as you've illustrated. Maxima's solve program produces the illustrated form when it cannot solve any better. It is presumably a feature. Also a feature: It does not produce extraneous solutions and check them afterwards, at

[sage-devel] Re: solve an algebraic expression

2011-05-15 Thread achrzesz
Maybe the following workaround attempt will be helpful? var('x,mp,me') eq=mp-sqrt(x^2+me^2)==x assume(mp>0) solve(eq^2,x) [x == 1/2*(me^2 - mp^2)/mp, x == -1/2*(me^2 - mp^2)/mp] On 15 Maj, 01:34, Dox wrote: > Hi again list, > > This time I come with a problem of solving an algebraic expression