global class ClosePosEveryDay implements database.Batchable<sObject>{
 global database.QueryLocator start(database.BatchableContext bc){
    String query;
    date todayDate=date.today();
    System.debug('Today Date------------->'+todayDate);
    System.debug('System Date------------->'+System.today());
    query='select id,Status__c from position__c where Status__c=\'Closed\' and createdDate<=:todayDate'+'+1';
    System.debug('Query------------->'+query);
    return Database.getQueryLocator(query);
    }
    global void execute(database.BatchableContext bc, List<position__c> scope){
    System.debug('Scope------------->'+scope);
    for(position__c posRec:scope){
    posRec.Status__c='Closed';
   
    }
    Database.update(scope,false);
    }
    global void finish(database.BatchableContext bc){
    }
    }
in this above cod i want to add 1 to todayDate variable in that query only. this code throwing an error. pleas give me answer