Evaluate the following integral ∫_a^blnx/x dx
All Answers
total answers (1)
total answers (1)
Mathematics
∫_a^blnx/x dx let u=lnx→du=dx/x
need an explanation for this answer? contact us directly to get an explanation for this answer∴x=a→u=lna,x=b→u=lnb
∴I=∫_lna^lnbu du=├ 1/2 u^2 ┤|_lna^lnb = 1/2 [(lnb )^2-(lna )^2 ]
=1/2 [(lnb-lna )(lna+lnb ]=1/2 ln(b/a) ln(ab)