解答题
9.计算
【正确答案】令
=t，则
∫ln(1+
)dx=∫ln(1+t)d(t2)=t2ln(1+t)-
=t2ln(1+t)-
=t2ln(1+t)-
+t-ln｜t+1｜+C
=(x-1)ln
=t，则∫ln(1+
)dx=∫ln(1+t)d(t2)=t2ln(1+t)-=t2ln(1+t)-
=t2ln(1+t)-+t-ln｜t+1｜+C=(x-1)ln
【答案解析】