Юлия t = x - 3 --> lim((sin(t + 3)/sin(3))^(1/t) = lim(1 + (2sin(t/2)cos(t/2 + 3)/sin(3)))^(1/t) = lim(1 + t*ctg(3))^(1/t) = e^(t*ctg(3)/t) = e^(ctg(3)).