不定積分dt/1+√t

不定積分dt/1+√t

∫〔1/(1+√t)〕dt
=2∫〔√t/(1+√t)〕d(√t)
=2∫〔(1+√t-1)/(1+√t)〕d(√t)
=2∫d(√t)-2∫〔1/(1+√t)〕d(√t)
=2√t-2ln(1+√t)+C