How to evaluate 1∫0ln(x)(1+ln(x)+ln(1−x))2x+1dx
How to evaluate +1dx
1
∫
0
ln(x)(1+ln(x)+ln(1−x))
2
x
In[]:=
ClearAll["Global`*"]
In[]:=
Hyperlink["evaluate int","https://math.stackexchange.com/questions/4832089/how-to-evaluate-int-0-1-frac-ln-x1-lnx-ln1-xx21dx"]
Out[]=
◼
Integrand
In[]:=
f[x_]:=+1
Log[x](1+Log[x]+Log[1-x])
2
x
In[]:=
Plot[f[x],{x,0,1}]
Out[]=
In[]:=
F[x_]=∫f[x]x
Out[]=
--Log[1-x]Log[x]+Log[1+x]Log[x]-Log[1-x]+Log[1+x]-Log[-x](-2Log[1-x]+Log[-x])Log[1+x]-Log+(-+x)+Log[-x]LogLog[1+x]-Log+(-+x)+Log[1-x]Log[x]Log+(-+x)+Log-Log+Log+(-+x)+Log[x](-2Log[1-x]+Log[x])Log[1-x]-Log-(+x)-Log[x]LogLog[1-x]-Log-(+x)-Log[1-x]Log[x]Log-(+x)-Log+Log-(+x)-Log+Log[x]-LogPolyLog2,--(-1+x)-Log[x]-LogPolyLog2,-+(-1+x)+PolyLog[2,-x]+2Log[x]PolyLog[2,-x]+Log[1-x]+LogPolyLog[2,-x]-PolyLog[2,x]-2Log[x]PolyLog[2,x]-Log[1-x]+LogPolyLog[2,x]-LogPolyLog2,-PolyLog2,+LogPolyLog2,-PolyLog2,-PolyLog3,--(-1+x)+PolyLog3,-+(-1+x)-3PolyLog[3,-x]+3PolyLog[3,x]-PolyLog3,+PolyLog3,
1
2
2
Log[x]
2
Log[x]
1
2
1
2
2
(1+)x
-1+x
1
2
2
1
2
2
1
2
2
Log
(1+)x
-1+x
1
1-x
1+x
1-x
1
2
2
1
2
1
2
2
(1-)x
-1+x
1
2
2
1
2
2
1
2
2
Log
(1-)x
-1+x
1
1-x
1
2
2
(+x)
-1+x
(1+)x
-1+x
1
2
2
(1-)x
-1+x
1
2
2
(1+)x
-1+x
(1-)x
-1+x
(1-)x
-1+x
x
-1+x
(1-)x
-1+x
(1+)x
-1+x
x
-1+x
(1+)x
-1+x
1
2
2
1
2
2
(1-)x
-1+x
(1+)x
-1+x
In[]:=
F0=F[x]
x
+
0
Out[]=
1
64
2
π
1
2
2
1
2
2
1
2
2
1
2
2
1
2
2
2
Log[-1-]
1
2
2
1
2
2
2
Log[2]
1
2
2
1
2
2
1
2
2
1
2
2
In[]:=
F1=F[x]
x
-
1
Out[]=
1
192
3
π
2
Log[1-]
1
2
2
2
π
1
2
2
2
Log-
1
2
2
3
Log-
1
2
2
3
Log[1-]
2
Log[1-]
2
Log[2]
2
Log[2]
In[]:=
ΔF=F1-F0//Simplify
Out[]=
1
192
3
π
2
π
1
2
2
1
2
2
1
2
2
2
Log[1-]
1
2
2
1
2
2
1
2
2
2
Log[-1-]
1
2
2
3
Log-
1
2
2
3
Log[1-]
2
Log[2]
1
2
2
2
Log[2]
2
Log[2]
2
Log[1-]
1
2
2
2
Log-
1
2
2
1
2
2
1
2
2
1
2
2
◼
Result
In[]:=
dF=ΔF//Re//ComplexExpand//FullSimplify
Out[]=
1
128
3
π
2
Log[2]
1
2
2
1
2
2
◼
Numerical value of Result
In[]:=
N[dF,20]
Out[]=
1.30259920452418087031+0.×
-21
10
◼
Verify with numerical integration
In[]:=
NIntegrate[f[x],{x,0,1},WorkingPrecision->20]
Out[]=
1.3025992045241808709