21

3

I entered a command incorrectly as follows:

```
DSolve[{y'[x]=y[x]},y[x],x]
```

I am now experiencing:

```
DSolve[{y'[x] == y[x]}, y[x], x]
```

During evaluation of In[26]:= DSolve::deqn: Equation or list of equations expected instead of True in the first argument {True}. >>

```
(* DSolve[{True},y(x),x] *)
```

How do I recover from this error. I've tried `Clear[y'[x]]`

. That didn't work.

3

`Remove[y]`

will do the trick. – ciao – 2014-01-13T06:25:49.847That worked! Thanks. – David – 2014-01-13T06:43:56.493

Related: (373)

– Mr.Wizard – 2014-01-13T08:09:16.310@rasher I caution against using

`Remove`

here! It will break any definitions that reference`y`

, and it will alter even localized appearances of the Symbol, though the definitions may still work. Try e.g.`fn[y_] := Sin[y]; Remove[y]; Definition[fn]`

– Mr.Wizard – 2014-01-13T08:34:50.870@Mr.Wizard: Good point. Probably gave too quick-n-dirty, emphasis on dirty, solution. – ciao – 2014-01-13T08:38:08.137