Concept:The integral simplifies by substituting x=tant, which converts the inverse trigonometric expressions into simple algebraic forms.Explanation:Let I=∫1+x2etan−1x[(sec−11+x2)2+cos−1(1+x21−x2)]dx Put x=tant, so t=tan−1x. Then dx=sec2tdt and 1+x2=sec2t. Also, 1+x2=sect, and since x>0, we have sec−1(sect)=t. And 1+x21−x2=1+tan2t1−tan2t=cos2t Thus cos−1(cos2t)=2t. The integral becomes I=∫et[t2+2t]dt Using the property ∫et[f(t)+f′(t)]dt=etf(t)+c with f(t)=t2, we get I=ett2+c Substituting back t=tan−1x gives I=(tan−1x)2etan−1x+cAnswer:Option B: (tan−1x)2etan−1x+c, where c is a constant of integration.