# Bug in sage solve

Sage raises an error when I try to solve the following:

`solve(a*exp(k*2) - n, a*exp(k*8)-m, a, k, solution_dict=True)`

What is the reason for this?

1

You need to define the variables using the `var`

command. Also, the syntax for `solve`

is slightly different.

```
var('a k n m')
solve([a*exp(k*2) - n==0, a*exp(k*8)-m==0], [a, k], solution_dict=True)
```

Unfortunately, Sage (which uses Maxima for this) does not solve the equation.

However, sympy does a nice job of solving here.

```
var('a k n m')
import sympy as sp
sp.solve([a*exp(k*2) - n, a*exp(k*8)-m], [a, k],dict=True)
```

Asked: **
2016-05-21 02:09:31 -0600
**

Seen: **33 times**

Last updated: **May 21 '16**

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