How to Find Beginning and End of Week

drop function find_beg_of_week 
go

create function find_beg_of_week (@week_number int, @today datetime) returns datetime
as
	begin
	declare @start_week datetime
	
	set @today = dateadd(wk, @week_number- datepart(wk,@today), @today)
	set @start_week =  dateadd(d, 1 - DATEPART(dw, @today), @today) 

	return @start_week 
	end
go


drop function find_end_of_week 
go

create function find_end_of_week (@week_number int, @today datetime) returns datetime
as
	begin
	declare @end_week datetime
	declare @start_week datetime

	set @today = dateadd(wk, @week_number- datepart(wk,@today), @today)
	set @start_week =  dateadd(d, 1 - DATEPART(dw, @today), @today) 
	set @end_week = dateadd(d,6,@start_week )
	return @end_week 
	end
go


select dbo.find_beg_of_week(1,getdate()), dbo.find_end_of_week(1,getdate())