Cyclohexene is treated with mCPBA and the product is then heated with dilute aqueous $\mathrm{H}{}_2\mathrm{SO}{}_4$. The final product is

Epoxidation gives cyclohexene oxide. Water attacks the protonated epoxide from the face opposite the C-O bond that breaks (anti opening), so the two OH groups end up trans. Attack at either carbon gives the (1R,2R) and (1S,2S) enantiomers in equal amounts, so the diol is racemic trans-cyclohexane-1,2-diol.