int 1/(t^2 + 2) dt = | t = 2^(1/2) * u, u = t/2^(1/2), dt = 2^(1/2) du | =
= int 1/(2 * u^2 + 2) * 2^(1/2) du = 2^(1/2) * int 1/(2 * (u^2 + 1)) du =
= 2^(1/2)/2 * int 1/(u^2 + 1) du = 1/2^(1/2) * arctg u + C =
= | u = t/2^(1/2) | = 1/2^(1/2) * arctg (t/2^(1/2)) + C