Résumé:
Our thesisisdevotedtosolvingasignificantandchallengingissueinthequalitativetheory
of differentialsystemscalledthesixteenthHilbertproblem.Moreprecisely,weusethefirst
integralstodeterminethemaximumnumberoflimitcyclesofsomefamiliesofdiscontinuous
piecewise nonlineardifferentialsystemsseparatedbyastraightline