20210212 14:07:07 +0200  received badge  ● Famous Question (source) 
20200228 03:59:46 +0200  received badge  ● Notable Question (source) 
20200228 03:59:46 +0200  received badge  ● Famous Question (source) 
20190303 22:42:38 +0200  received badge  ● Notable Question (source) 
20180718 12:49:42 +0200  received badge  ● Notable Question (source) 
20180324 09:43:14 +0200  received badge  ● Popular Question (source) 
20171128 07:08:25 +0200  received badge  ● Popular Question (source) 
20170801 15:25:34 +0200  received badge  ● Student (source) 
20170123 18:00:06 +0200  received badge  ● Popular Question (source) 
20170115 14:49:34 +0200  received badge  ● Famous Question (source) 
20160919 09:37:46 +0200  received badge  ● Popular Question (source) 
20160918 22:51:22 +0200  received badge  ● Notable Question (source) 
20160802 02:45:40 +0200  received badge  ● Popular Question (source) 
20160225 11:45:54 +0200  received badge  ● Famous Question (source) 
20151119 11:02:26 +0200  received badge  ● Popular Question (source) 
20151119 11:02:26 +0200  received badge  ● Notable Question (source) 
20151020 21:32:38 +0200  received badge  ● Notable Question (source) 
20151020 21:32:38 +0200  received badge  ● Popular Question (source) 
20150327 04:10:10 +0200  marked best answer  Solving linear matrix equations Hi everybody, I'm new to Sage and I'm pretty confused with the solving of matrix equations, I didn't fully understand the guide. I've got these vectors: And i want to implement the equation: to isolate and obtain the value of How can I do that? Thank you very much 
20150114 10:41:20 +0200  commented answer  Transpose of a column vector Thank you for your reply. May I ask you what is the difference between a list and a vector? 
20150112 23:17:55 +0200  commented answer  Transpose of a column vector

20150112 23:17:55 +0200  received badge  ● Commentator 
20150112 19:04:10 +0200  asked a question  Transpose of a column vector Hi, I've got a column vector and I need to transpose it. But when i do:
I've also tried doing What is the problem here? Thank you 
20150112 13:57:17 +0200  commented answer  Derivative of a function Thank you so much!! 
20150112 12:52:24 +0200  asked a question  Derivative of a function Hi, I've got this two functions: but it says No differentiation variable specified how can I derivate psi? Please someone help me it's driving me crazy since yesterday! Thank you very much 
20150111 22:34:34 +0200  commented answer  Equations solving Now the problem is that when i do What's wrong? 
20150111 22:29:02 +0200  commented answer  Equations solving Ok i got it, i just had to write 
20150111 22:25:55 +0200  commented answer  Equations solving I redefined eqq1, but doing like this it ignores the left part of the equation, so eqq1 becomes just sin(delta(t))*v/cos(delta(t)) 
20150111 21:27:36 +0200  commented answer  Equations solving It works! Grazie mille! ;) Now i substituted that value in the second equation doing
but when i do
it gives me diff(psi(t))=V_f*sin(delta(t))/l like i never did that substitution before. What can i do to have diff(psi(t))=[v(t)*tan(delta(t))]/l as a solution? 
20150111 20:16:36 +0200  asked a question  Equations solving Hi everybody, i've got this two equations: I need to isolate V_f from the first equation, obtaining V_f=v(t)/cos(delta(t)) and substitute it in the second equation. Then i have to isolate diff(psi(t))=[v(t)*tan(delta(t))]/l. I did : but it says "AttributeError: 'Sequence_generic' object has no attribute 'right'" How can i solve this two equations? Thank you. 
20141223 10:49:42 +0200  edited question  Sum of two vectors Hi everybody, i've got this functions and variables: where R is a matrix and a_V_ra is the vector [cos(psi(t))v(t), sin(psi(t))v(t),0]. But when i do this: it says: TypeError: unsupported operand parent(s) for '+': 'Full MatrixSpace of 3 by 1 dense matrices over Symbolic Ring' and 'Vector space of dimension 3 over Symbolic Ring' I guess it's saying that i'm summing a matrix and a vector, but they're both vectors! What can I do to make it work? Thank you. 
20141223 10:49:24 +0200  received badge  ● Editor (source) 