求∫dx/[(x-1)^(1/3)*(x+2)^(2/3)]不定积分
1个回答
展开全部
可乱消脊以先把x+2提出来
1/[(x-1)^(1/3)*(x+2)^(2/3)]
=1/(x+2)
*
[(x+2)/(x-1)]^(1/3)
做换元哗渗,令t=[(x+2)/(x-1)]^(1/3)
则x=1
+
3/(t^3-1)
dx=9t^2dt/(t^3-1)^2
代入原式得
∫3
/
[t(t^3-1)]
dt
=∫
-3/t
+
1/(t-1)
+
(2t+1)/(t^2+t+1)
dt
=-3ln|t|
+
ln|t-1|
+
ln(t^2+t+1)
+
C
再把t=[(x+2)/桥宏(x-1)]^(1/3)代入即可
1/[(x-1)^(1/3)*(x+2)^(2/3)]
=1/(x+2)
*
[(x+2)/(x-1)]^(1/3)
做换元哗渗,令t=[(x+2)/(x-1)]^(1/3)
则x=1
+
3/(t^3-1)
dx=9t^2dt/(t^3-1)^2
代入原式得
∫3
/
[t(t^3-1)]
dt
=∫
-3/t
+
1/(t-1)
+
(2t+1)/(t^2+t+1)
dt
=-3ln|t|
+
ln|t-1|
+
ln(t^2+t+1)
+
C
再把t=[(x+2)/桥宏(x-1)]^(1/3)代入即可
推荐律师服务:
若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询