my question is on initial value problem for ODE's..

iv been asked to solve the following IVP:

dx/dt = (x^2)*(cos 2t) for x(pi/4)=0

Basically iv rearranged this and integrated to get

-1/x = 1/2*sin2t + c

But the problem came when i had to put in the values for x and t, when i plug x into the equation, i get -1/0, for which i cant do ....urm i dont know what to do next ...any help?? thankz