## #2798 asking ridiculous irritating questions again and fails to do a straightforward known integral

None
closed
nobody
None
5
2014-08-25
2014-08-13
dan hayes
No

wxMaxima version: 13.4.0
Maxima version: 5.31.1
Maxima build date: 2013-09-24 09:49:12
Host type: i686-pc-mingw32
Lisp implementation type: GNU Common Lisp (GCL)
Lisp implementation version: GCL 2.6.8

```(assume(positive,true),assume_pos_pred:true,assume(a>0),assume(u>0,mo>0,m>0),t1:exp(-(k-y)^2-(-mo*k+m*y)^2)*exp(-u*y^2)
,t1i:ratsimp(integrate(t1,y,-inf,inf)),t2i:ratsimp(integrate(t1i,k,-inf,inf))
,ldisp(["t1",t1,"integrate wrt",y,t1i,"over",k,t2i]))
```

asks: `is (mo^2+1)*u+mo^2 - 2*mo*m + m^2 positive , negative or zero ?`

I answer the ridiculous question and still does not do the straightforward integral.

NOw i put in two commands which i used to facilitate the simple solution but which are NOwhere used and comes back with the answer WHY ?
NOWHERE is the information tt:... NOR tti:... referred in this following

```(t1:exp(-(k-y)^2-(-mo*k+m*y)^2)*exp(-u*y^2),t1i:factor(integrate(t1,y,-inf,inf))
, tt:ratsimp(diff(t1i,k)/2/k/t1i) , tti:integrate(exp(k^2*tt),k,-inf,inf) , t2i:ratsimp(integrate(t1i,k,-inf,inf))
,ldisp(["t1",t1,"integrate wrt", y , t1i , "over", k , t2i]))
```

## Discussion

• Robert Dodier - 2014-08-15

Adding 4 tildes to format code bits. Would be nice if the author of the report would do so himself.

• Robert Dodier - 2014-08-15
• Description has changed:

Diff:

```--- old
+++ new
@@ -5,17 +5,21 @@
Lisp implementation type: GNU Common Lisp (GCL)
Lisp implementation version: GCL 2.6.8

+~~~~
(assume(positive,true),assume_pos_pred:true,assume(a>0),assume(u>0,mo>0,m>0),t1:exp(-(k-y)^2-(-mo*k+m*y)^2)*exp(-u*y^2)
,t1i:ratsimp(integrate(t1,y,-inf,inf)),t2i:ratsimp(integrate(t1i,k,-inf,inf))
,ldisp(["t1",t1,"integrate wrt",y,t1i,"over",k,t2i]))
+~~~~

-asks: is (mo^2+1)*u+mo^2 - 2*mo*m + m^2  positive , negative or zero ?
+asks: `is (mo^2+1)*u+mo^2 - 2*mo*m + m^2  positive , negative or zero ?`

I answer the ridiculous question and still does not do the straightforward integral.

NOw i put in two commands which i used to facilitate the simple solution but which are NOwhere used and comes back with the answer WHY ?
NOWHERE is the information tt:... NOR tti:... referred in this following

+~~~~
(t1:exp(-(k-y)^2-(-mo*k+m*y)^2)*exp(-u*y^2),t1i:factor(integrate(t1,y,-inf,inf))
, tt:ratsimp(diff(t1i,k)/2/k/t1i) , tti:integrate(exp(k^2*tt),k,-inf,inf) , t2i:ratsimp(integrate(t1i,k,-inf,inf))
,ldisp(["t1",t1,"integrate wrt", y , t1i , "over", k , t2i]))
+~~~~
```

• Robert Dodier - 2014-08-25
• status: open --> closed

• Robert Dodier - 2014-08-25

I've tried to figure out what this report is about and wasn't able to figure it out. My advice is to submit a new report which focuses on a single clear example.