Ask Your Question

exponential equation

asked 2010-10-02 06:35:11 -0500

amalea gravatar image

updated 2011-04-28 11:59:57 -0500

Kelvin Li gravatar image

sage: solve(exp(-x)+exp(x) == 2,x) [x == 0] sage: solve(exp(-2x)+exp(2x) == 2,x) []

Can tell me anyone why the second equation has no solution?

edit retag flag offensive close merge delete


For the record, this question is closely related to

Kelvin Li gravatar imageKelvin Li ( 2011-04-28 12:00:41 -0500 )edit

1 answer

Sort by ยป oldest newest most voted

answered 2010-10-02 15:47:01 -0500

kcrisman gravatar image

I unfortunately don't have time to check why this doesn't work, but the following keyword argument (useful to know in any case) does work:

sage: (exp(-2*x)+exp(2*x) == 2).solve(x,to_poly_solve=True)
[x == I*pi*z15]

which should be interpreted as saying z15 is a free integer variable (hence z). One can also do

sage: (exp(-x)+exp(x) == 2).solve(x,to_poly_solve='force')
[x == 2*I*pi*z24]

for all possible solutions to the original one. Unfortunately, finding the documentation for this (currently) requires using the method notation instead of functional

sage: solve?


edit flag offensive delete link more

Your Answer

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

Add Answer

Question Tools


Asked: 2010-10-02 06:35:11 -0500

Seen: 1,314 times

Last updated: Oct 02 '10