sentence1: If three variables , formula _ 26 , formula _ 27 and formula _ 28 are bound by the condition formula _ 29 for some differentiable function formula _ 30 , then the following total differentials exist
sentence2: If three variables , Formula 26 , Formula 27 and Formula 28 are bound by condition formula 29 for a total function formula 30 , then the following differentials exist .