Infinitive complement

• find: A digest has the following properties: It should be computationally infeasible to find another input string that will generate the same digest.

Used with adjective complement

• become: However, this approach would very quickly become infeasible with more than a few parameters.

• prove: The nationwide metadata enhanced search engine proved infeasible, federated metadata initiatives were not.

• seem: In this situation, political resolution of the issue by means of an administrative ballot recount seemed infeasible.

Modifying Another Word

• computationally: A digest has the following properties: It should be computationally infeasible to find another input string that will generate the same digest.

• politically: However, an outright ban on smoking is politically infeasible, given concerns for civil liberties.

Modifies a noun

• solution: How to get rapid convergence in the vicinity of a locally infeasible solution.