5
votes
3answers
876 views

Assign output of solve to variables [duplicate]

I have this input: Solve[x^2 + 3 x + 2 == 0, x] which gives this output: {{x -> -2}, {x -> -1}} I want the first x ...
2
votes
1answer
467 views

How to use output from previous line in Plot? [duplicate]

Suppose, I want to solve a equation and want to obtain it's first root. In this case I've used In[1]=:Solve[b^2 + b*z + 1 == 0, b][[1]] This gives ...
0
votes
3answers
122 views

beginner's question: change a parameter while get variable answers [duplicate]

I'm new to Mathematica from R, since R is not quite good at dealing with the following problem. Say, i want to solve the function a x - 10 = 0. Each time I change the value of a, say, from 1 to 10 by ...
1
vote
1answer
714 views

How to extract Solve results as variables [duplicate]

Possible Duplicate: Assign the results from a Solve to variable(s) In the following example: ...
4
votes
1answer
231 views

Check if an inequality holds among the solutions returned by Solve [duplicate]

Let's say I solve a system: Solve[{a == 3* c, b == 2 *a}, {a, b}] and then want to see if the values found for a and ...
0
votes
2answers
170 views

How to get a number from Solve [duplicate]

It's often useful to get just one number from Solve. I use the following construction for acquiring one solution from the expression returned by ...
0
votes
1answer
295 views

Assign the result of Solve in a list [duplicate]

Possible Duplicate: Assign the results from a Solve to variable(s) I want to assign the results of a Solve command in a list. For example Solve[-((287 s^3)/50) == 0, s] returns {{s -> 0}, ...
0
votes
0answers
158 views

Assigning the answer of Solve to a variable [duplicate]

If I enter Solve[(x-2)(x+2)==0,x] then the answer comes up as {{x -> 2}, {x -> -2}} I want to make two variables ...
0
votes
0answers
151 views

The /. syntax in numerical methods [duplicate]

I have an analytical approximation method for solving an ODE and want to compare this to an NDSolve solution, but the syntax is confusing me. To get the solution from NDSolve, I define the ODE as eqn ...
0
votes
0answers
139 views

How to assign equation solutions to variables [duplicate]

I have 12x12 Matrix with which I have to solve the equation below: ...
0
votes
1answer
108 views

How to convert the expression '{a->a0, b->b0}' to the expression 'a=a0; b=b0'? [duplicate]

How to convert the expression '{a->a0, b->b0}' to the expression 'a=a0; b=b0'? I think this is a common question and do not know if someone has asked it before. Any help or suggestion will be ...
0
votes
1answer
103 views

Error when solving equations constructed with Table [duplicate]

I have a couple of questions about the problem I am trying to solve ...
1
vote
1answer
59 views

Assigning solutions to a variable [duplicate]

If I do Solve[x+1==0, x] then I get {{x -> -1}} But I want to assign the solution -1 directly before seeing the result, ...
0
votes
1answer
58 views

How do I assign the solutions of an equation to separate variables? [duplicate]

I'm a beginner to Mathematica. Here's my question. I'd like to store the output(s) of a Solve command to variable(s) that can be manipulated later. For example, I would like x1 and x2 to be the two ...
0
votes
1answer
43 views

Storing solution to x and y [duplicate]

If I do sol=Solve[{2x+2==y,3x+9==y},{x,y}] then Mathematica will tell me {{x -> -7, y -> -12}} But I would like to ...

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