Ask Your Question

What does r in an answer mean

asked 2020-08-07 12:19:19 +0100

cybervigilante gravatar image

updated 2020-08-07 13:25:11 +0100

slelievre gravatar image

After I ran the following I got a valid image but what do the r's stand for in the solve part? They don't seem to have a value but I didn't get an error.

var('x y')
show(plot3d(x^2 + y^2, (x,-2,2), (y,-2,2)))


solve(x^2 + y^2==0,[x,y])
[[x == r1, y == I*r1], [x == r2, y == -I*r2]]
edit retag flag offensive close merge delete


For some reason the y answer is sqrt(-1) times r1, etc, but isn't showing up in my query.

cybervigilante gravatar imagecybervigilante ( 2020-08-07 12:23:59 +0100 )edit

1 Answer

Sort by ยป oldest newest most voted

answered 2020-08-07 12:31:04 +0100

slelievre gravatar image

updated 2020-08-07 13:23:37 +0100

Sometimes solving an equation gives a family of solutions with one or more parameters.

Complex-valued parameters are denoted by c1, c2, etc.

Real-valued parameters are denoted by r1, r2, etc.

Integer-valued parameters are denoted by z1, z2, etc.


sage: solve (x - x == 0, x)
[x == r1]
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

1 follower


Asked: 2020-08-07 12:19:19 +0100

Seen: 530 times

Last updated: Aug 07 '20