Help evaluating integral - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: HP Prime (/forum-5.html) +--- Thread: Help evaluating integral (/thread-12714.html) Help evaluating integral - kevin3g - 03-31-2019 02:16 PM Say I already know the antiderivative, F(x), and want to find the area between 2 and 3. Is there a way to do F(2)-F(3) without plugging in the function twice? RE: Help evaluating integral - toshk - 03-31-2019 06:40 PM [attachment=7083] RE: Help evaluating integral - parisse - 03-31-2019 06:48 PM preval RE: Help evaluating integral - Wes Loewer - 04-01-2019 05:14 PM (03-31-2019 06:48 PM)parisse Wrote:  preval The 50g had a PREVAL and I figured it meant PR EVALuate, but I always wondered what the "PR" stood for. Is it a French abbreviation? RE: Help evaluating integral - parisse - 04-01-2019 05:26 PM pr stands for primitive, the French word for antiderivative. RE: Help evaluating integral - Wes Loewer - 04-01-2019 06:10 PM I learned something new today. I see that the English language https://en.wikipedia.org/wiki/Antiderivative mentions "primitive function" as well. I don't recall ever hearing this term before. Anybody know of any English language countries that use this term? RE: Help evaluating integral - dae - 08-23-2019 06:00 PM Be sure to purge(x) before using preval(F(x),a,b). If x has been assigned a value, F(x) will be evaluated using the current x value, before calculating F(b) - F(a). preval(x^2+x, 2, 3) outputs 6 only if x has not been assigned a value Similarly: f(x) := x^2+x preval(f(x), 2, 3) outputs 6 only if x has not been assigned a value If for instance, x has the value 1, preval(f(x),2,3) will output 0. Fortunately, if x is purged, then f(x) will revert to the symbolic expression without having to be re-entered. RE: Help evaluating integral - Aries - 08-24-2019 04:18 PM (03-31-2019 02:16 PM)kevin3g Wrote:  Say I already know the antiderivative, F(x), and want to find the area between 2 and 3. Is there a way to do F(2)-F(3) without plugging in the function twice? Ehm … you're talking about the first FTC ? Best, Aries