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3.5 Calculus • 69> Int (g(t), t=0..infinity);∫ ∞e (−a t) ln(t) dt0> value(%);lim − e(−a t) ln(t) + Ei(1, a t) + γ + ln(a)t→∞ aHere Maple assumes that the parameter a is a complex number. Hence,it returns a more general answer.For situations where you know that a is a positive, real number, indicatethis by using the assume command.> assume(a > 0):> ans := Int(g(t), t=0..infinity);∫ ∞ans := e (−a~ t) ln(t) dt0> value(%);− ln(a~)a~− γ a~The result is much simpler. The only non-elementary term is the constantgamma. The tilde (~) indicates that a carries an assumption. Removethe assumption to proceed to more examples. You must do this in twosteps. The answer, ans, contains a with assumptions. If you want to resetand continue to use ans, then you must replace all occurrences of a~with a.> ans := subs(a =’a’, ans );∫ ∞ans := e (−a t) ln(t) dt0The first argument, a = ’a’, deserves special attention. If you typea after making an assumption about a, Maple automatically assumes you