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logx-1-x-x-dx-please-help-this-




Question Number 49003 by mondodotto@gmail.com last updated on 01/Dec/18
∫((logx)/( (√(1−x^x ))))dx  please help this
logx1xxdxpleasehelpthis
Commented by maxmathsup by imad last updated on 01/Dec/18
I =∫   ((ln(x))/( (√(1−e^(xln(x)) ))))dx  changement xln(x)=t give (ln(x)+1)dx =dt  I =∫ ((ln(x)+1−1)/( (√(1−x^x ))))dx =∫  ((ln(x)+1)/( (√(1−e^(xlnx) ))))dx −∫   (dx/( (√(1−x^x ))))  =∫ (dt/( (√(1−t))))  −∫   (dx/( (√(1−x^x )))) =−2(√(1−t)) −∫ (dx/( (√(1−x^x )))) =−2(√(1−x^x )) −∫   (dx/( (√(1−x^x ))))  let find ∫   (dx/( (√(1−x^x ))))  at form of serie due to  0<x^x <1  we have (1+u)^α  =1+((αu)/(1!)) +((α(α−1))/(2!)) u^2  +....+((α(α−1)...(α−n+1))/(n!)) u^n  +... ⇒  (1−u)^α  =1−αu +((α(α−1))/(2!)) u^2   +((α(α−1)...(α−n+1))/(n!))(−1)^n u^n  +... ⇒  (1−x^x )^(−(1/2))  =1+(1/2) x^x   +(((−(1/2))(−(3/2)))/(2!)) x^(2x)  +...(((−(1/2))(−(3/2))...(−(1/2)−n+1))/(n!)) (−1)^n  x^(nx) +...  ⇒∫  (dx/( (√(1−x^x )))) =x +(1/2) ∫ x^x dx +∫  (3/(4 2!)) x^(2x) dx +...  +(((−(1/2))(−(3/2))....(−(1/2)−n+1))/(n!)) (−1)^(n )  ∫   x^(nx) dx+....
I=ln(x)1exln(x)dxchangementxln(x)=tgive(ln(x)+1)dx=dtI=ln(x)+111xxdx=ln(x)+11exlnxdxdx1xx=dt1tdx1xx=21tdx1xx=21xxdx1xxletfinddx1xxatformofseriedueto0<xx<1wehave(1+u)α=1+αu1!+α(α1)2!u2+.+α(α1)(αn+1)n!un+(1u)α=1αu+α(α1)2!u2+α(α1)(αn+1)n!(1)nun+(1xx)12=1+12xx+(12)(32)2!x2x+(12)(32)(12n+1)n!(1)nxnx+dx1xx=x+12xxdx+342!x2xdx++(12)(32).(12n+1)n!(1)nxnxdx+.
Commented by MJS last updated on 01/Dec/18
where did you find this?
wheredidyoufindthis?

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