You shouldn’t be taking log of t2. Rather, t2 takes the place of the log_sum_inv. Please study section 5.2.7 of https://docs.mosek.com/modeling-cookbook/expo.html#modeling-with-the-exponential-cone and see example CVX code at Log( {convex} ) . The only log term you should have should be of a constant, not a CvX variable or expression.