Question

高数不定积分题

求第一行变成第二行的详解，详细步骤

Answer 1

如图所示

Answer 2

4∫t^2/(t^2-1) dt
=4∫[1 + 1/(t^2-1)] dt
=4t +4∫ dt/(t^2-1)
=4t +2∫ [1/(t-1) -1/(t+1) ] dt
=4t+2ln|(t-1)/(t+1)| +C