解答题
14.求∫arctan(1+
【正确答案】令
=t，则
=∫arctan(1+t)d(t2)=t2arctan(1+t)－
=t2arctan(1+t)－
=t2arctan(1+t)－t+ln(t2+2t+2)+C
=
=t，则=∫arctan(1+t)d(t2)=t2arctan(1+t)－=t2arctan(1+t)－
=t2arctan(1+t)－t+ln(t2+2t+2)+C
=
【答案解析】