∫(0到ln2) xe^x dx
= ∫(0到ln2) x d(e^x)
= xe^x(0到ln2) - ∫(0到ln2) e^x dx
= (ln2*e^ln2)-(0*e^0) - e^x(0到ln2)
= ln2*2 - (e^ln2 - e^0)
= 2ln2 - 2 + 1
= 2ln2 - 1