Binary Search in TypeScript

This implementation of Binary Search includes both the iterative and recursive implementations for comparison:

class BinarySearch
{
   public binarySearchIterative(arr: number[], num: number) : number
   {
       let low = 0;
       let mid = 0;
       let high = arr.length - 1;

       while(low <= high)
       {
           mid = (low + high) / 2;

           if(num < arr[mid])
           {
               high = mid - 1;
           }
           else if(num > arr[mid])
           {
               low = mid + 1;
           }
           else
           {
               return mid;
           }
       }
       // Arbitrary value to signify non-existance.
       return -1;
   }

   public binarySearchRecursive(arr: number[], num: number) : number
   {
       return this.binarySearchRecursiveAux(arr, num, 0, arr.length - 1);
   }

   private binarySearchRecursiveAux(arr: number[], num: number, low: number, high: number)
   {
       const mid = (low + high) / 2;

       if(low >= high) return -1;

       if(num < arr[mid])
       {
           return this.binarySearchRecursiveAux(arr, num, low, mid - 1);
       }
       else if(num > arr[mid])
       {
           return this.binarySearchRecursiveAux(arr, num, mid + 1, high);
       }
       else
       {
           return mid;
       }
   }
}