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Integral with unexpected result - lrdheat - 05-30-2016 04:42 AM
In home, int ((e^x)/(ln x)) from .01 to 1 produces ~58.9
In CAS, [~-23.55 ~-86.48]
The integral should be infinite.
This on hand held version 10077
RE: Integral with unexpected result - lrdheat - 05-30-2016 04:43 AM
Correction...In home, the result is ~-58.92
RE: Integral with unexpected result - parisse - 05-30-2016 04:58 AM
It's impossible to get infinity by a numerical method (it would require finding an equivalent at x=1). The CAS displays a big warning in the terminal before returning two values that are not close at all, a clear sign that the values are garbage.
RE: Integral with unexpected result - cyrille de brébisson - 05-31-2016 04:44 AM
Hello,
In home, the numerical method does seem to converge to a solution
One of the "good" thing about the method used in home is that it never evaluates the function on the 'edges', so it can deal with a function that is not defined there...
but, for fast moving functions, this can lead to weird results.
Cyrille