The astute reader will note the difference in Maple's behavior here as opposed to that in Examples 4.5.1 and 4.5.2. In those examples, the integrands have a vertical asymptote at $x\&equals;0$, whereas this present integrand does not. In the first two examples, if $t<0$, the integration is from $x\&equals;1$ back across this vertical asymptote, an integration that is not permitted. Hence, in those two examples, Maple must know somehow that $t\&gt;0$.