A CD rotates from rest up to an angular speed of 32.40 radians per second in a time of 0.861 seconds. Determine the angle (in degrees) through which the disc turns while coming up to speed assuming that the tangential acceleration is uniform.

I hve tried omega = change in theta/change in time but I got it wrong any help? Thanks

ε= ω/t=32.4/0.861=37.63 rad/s²

φ=ω²/2ε=32.4²/2•37.63=13.95 rad=799.3°