int (1 3) x/(-2 * x^2 + 3) dx = -1/4 * int (1 3) (-4 * x)/(-2 * x^2 + 3) dx =
= -1/4 * int (1 3) d(-2 * x^2)/(-2 * x^2 + 3) =
= -1/4 * int (1 3) d(-2 * x^2 + 3)/(-2 * x^2 + 3) = | t = -2 * x^2 + 3 | =
= -1/4 * int (1 -15) dt/t = 1/4 * int (-15 1) dt/t =
= 1/4 * (ln |t|)_{-15}^{1} = 1/4 * (ln 1 - ln 15) = -1/4 * ln 15.