"be determined precisely" is a grammatically correct and commonly used phrase in written English.
It means to be accurately or exactly determined. Example: The location of the buried treasure was not known, but with the help of a map and compass, we were able to determine its location precisely.
Thus the side payments that rich countries will have to make to poor ones to adopt such technologies can't yet be determined precisely.
(In many of these cases, the amounts of lost deposits cannot be determined precisely, so the awards are estimated based on a study of similar accounts and adjusted for inflation).
The date of entry of the Indo-Aryans into the Indian subcontinent cannot be determined precisely, though the beginning of the 2nd millennium bce is plausible and generally accepted.
In the absence of any biological data from which the maximum limit of the span of life can be determined precisely, an estimate of the limit must be obtained from observation of the actual length of life of persons who already have died.
Parameters of a probabilistic model often cannot be determined precisely on the basis of limited data.
The extent of the genetic changes can then be determined precisely and the gene content of the affected regions established.
Its emergency braking had been applied before the collision, but it had not been determined precisely when.
(Colour was determined precisely using a colourimeter; a texture analyser bent and compressed each burger to work out how much it yielded).
In this case, the uncertainty of ITD is very small and is determined precisely.
In the foregoing analysis, the system's stability has been determined precisely using the interface impedance.
For simplicial complexes, these spectra are not always intervals, and the gaps are determined precisely.
