Hello,

Is there any way to optimized a a sum of customized exponential functions in CVX? Please, consider the following problem:

```
minimize(-(exp(a.x) + exp(b.y)))
subject to
L <= x <= U
M <= y <= N
x + y <= B
```

My variables are x and y while L, M, U, N, a, b and B are all constants.

Thanks.