focal chord of a conicfocal distancefocal lengthfocal planefocal pointfocal propertyfocal property of an ellipsefocal radiusfocalizationfocalizefocusfocus for a gauss mappingfocusedfoldfold applicationfoldedfoliumfolium of descartesfollowfollow fromfollow restfollowed byfollowingfootfootnoteforfor allfor all values offor all xfor completenessfor iffor instancefor our purposefor performingfor somefor sufficiently large valuesfor the casefor the reasonfor the sake offor this reasonfor typographical reasonsfor wheneverfor whichforbiddenforceforce polygonforcedforced ocillatory motionforced oscillationforced oscillations
