First Date and Last Date Of First Month And Previous Month

DECLARE @mydate DATETIME

SELECT @mydate = GETDATE()


SELECT CONVERT(VARCHAR(25),DATEADD(MONTH , -1,DATEADD(dd,-(DAY(@mydate)-1),@mydate)),101) AS FirstDateOfLastMonth

SELECT CONVERT(VARCHAR(25),DATEADD(dd,-(DAY(@mydate)),@mydate),101)  as LastDayOfPreviousMonth

SELECT CONVERT(VARCHAR(25),DATEADD(dd,-(DAY(@mydate)-1),@mydate),101) AS FirstDateOfCurrentMonth

SELECT CONVERT(VARCHAR(25),@mydate,101) AS  'PresentDateOfCurrentMonth-Today'