Error computing limits as x -> inf

[Joe Horn]

(10-09-2014 04:47 AM)Chris Pem10 Wrote:  Finding the limit of (2*x)/(x+1) as x -> infinity gives different results when computed in the CAS vs the HOME environments.

The CAS gives the correct answer: 2

The HOME environment gives (2*inf)/(inf + 1)

Both above results were computed on a physical calc.

The emulated calc gives the correct answer in the CAS, but returns the limit un-evaluated in the HOME environment.

Following the design philosophy that CAS is for exact symbolic math and Home is for floating-point approximations, it's more appropriate to use something like limit(2*X/(X+1),X,1ᴇ50) in Home to get the desired answer, using 1e50 as an "approximation for infinity".