How to get first day and last day Of the current and Previous year on Oracle

Get current year :

SELECT TO_CHAR(SYSDATE, 'YYYY')  AS Current_Year FROM DUAL;

First Day of Current Year:

SELECT TO_CHAR(TRUNC (SYSDATE , 'YEAR') ,'DD/MM/YYYY') FROM DUAL;

Last Day of Current Year:

SELECT TO_CHAR(ADD_MONTHS(TRUNC (SYSDATE ,'YEAR'),12)-1,'DD/MM/YYYY')  

      AS LastDay_Current_Year 

FROM DUAL;

First Day of Previous Year:

SELECT TO_CHAR(ADD_MONTHS (TRUNC (SYSDATE,'YEAR'), -12),'DD/MM/YYYY')  

   AS FirstDay_Previous_Year 

FROM DUAL;

 Last Day of Previous Year:

SELECT TO_CHAR(ADD_MONTHS (TRUNC (SYSDATE, 'YEAR'), -1 ) +30 ,'DD/MM/YYYY')  

     AS LastDay_PreviousYear

FROM DUAL;