If x = 3 + 2√2 and xy = 1, then the value

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x = 3 + 2√2
⇒ xy = 1

⇒ y =	1	=	1	×	3 - 2√2
	3 + 2√2		3 + 2√2		3 - 2√2

=	3 - 2√2	= 3 - 2√2
	9 - 8

∴ x + y
= 3 + 2√2 + 3 - 2√2 = 6

∴	x² + 3xy + y²	=	(x + y)² + xy
	x² - 3xy + y²		(x - y)² - 5xy

=	36 + 1	=	37
	36 - 5		31

If x = 3 + 2√2 and xy = 1, then the value of	x² + 3xy + y²	is
	x² − 3xy + y²