U = (e^t/2)^ln(t-1) = e^(ln(t-1)*(t/2))
u = e^(ln(t-1)*(t/2)) * (ln(t-1)*(t/2))
(ln(t-1)*(t/2)) = (t/2)/(t-1) + ln(t-1)/2
u = e^(ln(t-1)*(t/2)) * (ln(t-1)*(t/2)) =
= e^(ln(t-1)*(t/2)) * ((t/2)/(t-1) + ln(t-1)/2) = [t = 2] =
= e^(0 * 1 * (1 + 0)) = e^0 = 1