This time XCAS and hp prime are really wrong! ! !

12282018, 04:06 PM
(This post was last modified: 12282018 04:15 PM by yangyongkang.)
Post: #1




This time XCAS and hp prime are really wrong! ! !
Sorry, I am picking up XCAS or hp prime again. The first few times I wrote is the problem that hp prime or XCAS can't solve. This time I pointed out that hp prime or XCAS is really wrong. The prototype is to calculate int(abs(sin(x)/e^x), x, 0, +infinity). We know that the integrand removes the absolute value and becomes int(sin(x)/e^x,0, +infinity), using the NewtonLeibnitz formula is very good, XCAS gives an answer of 1/2, in fact the answer is correct, but after adding the absolute value, the XCAS answer is still given 1/2. Obviously wrong. We enter on Wolfram Mathematica 11.3
Code: Integrate[Abs[Sin[x]/E^x], {x, 0, Infinity}] Code: FullSimplify[%] Code: 1/2 Coth[\[Pi]/2] In addition, in fact, hp prime or XCAS can give int(e^(x^2), x), and should also give int(sin(x)/e^(x^2), x) , but unfortunately, XCAS returned to the original study hard, improve every day 

« Next Oldest  Next Newest »

Messages In This Thread 
This time XCAS and hp prime are really wrong! ! !  yangyongkang  12282018 04:06 PM
RE: This time XCAS and hp prime are really wrong! ! !  parisse  12282018, 06:40 PM
RE: This time XCAS and hp prime are really wrong! ! !  yangyongkang  12292018, 12:55 PM

User(s) browsing this thread: 1 Guest(s)