Its not quite a bad as it looks: when you separate the variables, you get the following equation
dy/(y - 1/y) = t dt or y dy/(y2 - 1) = t dt to obtain
(1/2)ln(y2 - 1) = t2/2 + Constant or ln(y2 - 1) = t2 + Constant
or y2 - 1 = Ket2 (K = Constant) then y = SQRT(Ket2 + 1)
To satisfy y(0) = 3 means that K = 8 and y = SQRT(8et2 + 1)