Question

Calculando a integral ∫tcos tdt

Answer 1

$\int\limits{tcos(t)} \, dt$

u = t             $du=dt$

dv = $cos(t)dt$      $v=sen(t)$

$uv-\int\limits {vdu} \, \\\\t.sen(t)-\int\limits{sen(t)} \, dt\\\\t.sen(t)+cos(t)+C$