Show that $2(\sin y + 1)(\cos y + 1) = (\sin y + \cos y + 1)^2$ The question states:

Show that: $$2(\sin y + 1)(\cos y + 1) = (\sin y + \cos y + 1)^2$$

This is what I have done 
$2(\sin y + 1)(\cos y + 1) = 2(\sin y + \cos y + 1)^2$
L. H. S.                = R. H. S.
From L. H. S.
$2(\sin y +1)(\cos y + 1) = 2(\sin y\cos y + \sin y + \cos y + 1)$
$= 2(\sin y\cos y + \sin y + \cos y + \sin^2 y + \cos^2 y)  (\sin^2 y + \cos^2 y = 1)$
$= 2(\sin^2 y + \sin y\cos y + \sin y + \cos^2 y + \cos y)$
I got stuck here. I do not know what to do from here. 
I have tried and tried several days even contacted friends but all to no avail.

Expanding the RHS,
$$\color{blue}{(\sin y + \cos y + 1 )^2} = \sin^2 y + \cos^2 y +  1 +2\cos y \sin y + 2\cos y + 2\sin y$$
$$= 1+ 1 +2\cos y \sin y + 2\cos y + 2\sin y=2(1+\cos y \sin y + \cos y + \sin y) = 2 \left[(1+\cos y) + (\sin y + \cos y \sin y ) \right] = 2 \left[(1+\cos y) + \sin y(1 + \cos y) \right]=\color{blue}{2(1+\cos y)(1+\sin y )}$$
