can the prime really not solve this integral?

[rkf]

(02-27-2014 07:08 PM)parisse Wrote:  We almost never test the CAS in degree mode, therefore more bugs are expected there. The reason here is that for numeric integration with an infinite boundary you must make a change of variable, here we set tan(y)=x for y in 0..pi/2, dx=(1+tan(y)^2)*dy ... except that in degree mode you must add a pi/180 factor.

Interestingly enough, both HP50g, and TI-92 Plus, give a numerically correct approximation to the exact answer (pi^4/15) independent of the degree/radiant setting :-)