How to find last day of the past month and First day of the past Month

Requirement:- To find last day of the previous month and First day of the previous Month.

Solution: 

1) This can be achieved using TRUNC function as below.

SELECT TRUNC(TRUNC(SYSDATE, 'MM') - 1, 'MM') "FIRST DAY OF PREVIOUS MONTH",
                TRUNC(SYSDATE, 'MM') - 1 "LAST DAY OF PREVIOUS MONTH" ,                         TRUNC(SYSDATE) "Today Date"   FROM DUAL






2)  Can be achieved using "ADD_MONTHS and LAST_DAY" function as below.

   SQL>SELECT TRUNC(LAST_DAY(ADD_MONTHS(sysdate,-1))) from dual