Ask Your Question

# Solve a system of nonlinear equations

I'm trying to solve the following system of nonlinear equation:

var("x,L,a")
sms = (x/(1-L))^(1-a) == .3
bb = x == .3*L
solve([sms,bb],x,L)


I expect that sage gives me a symbolic solution, the output is the following:

[x == 0.3*L, (-x/(L - 1))^(-a + 1) == 0.3]


As I am a newbie to sage, I wonder if there's something wrong/missing

edit retag close merge delete

## 1 Answer

Sort by » oldest newest most voted

Since bb is fairly simple, you can substitute that into sms. Then, solving gives something nice. However, you have to tell Sage some information about a.

var("x,L,a")
assume(a>0)
assume(a<1)
sms = (x/(1-L))^(1-a) == 3/10
bb = x == 3/10*L
solve(sms.subs(bb),L)

more

## Comments

I have a similar problem where my version of bb is not so simple and (sms == sms.subs(bb)) is true. Does a different method exist to solve the problem?

I suggest creating a separate post and giving some example code so we can see exactly what you are working with.

## Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

## Stats

Asked: 2015-05-06 20:26:34 +0200

Seen: 471 times

Last updated: May 07 '15