Question

( (x y)^{2}=2left(x^{2}+y^{2}right) )
( x^{2}+y^{2}+2 x y=2 x^{2}+2 y^{2} )
( x^{2}+y^{2}-2 x y=0 )
( quad(x-y)^{2}=0 )
So ( [x=y] )( quad(x-y+1)^{2}=4 )
( (0+1)^{2}>4 )
( 4=pm 2 )
( 6 u+100 ) so 122

# (U) UJ (B) 64 (A) 63 (D) 4 If (x + y)2 = 2(x2 + y2) and (x - y + 2)2 = 4,2 > 0, then 2 is equal to : (C) 3 (A) 1 (B) 2 Ihinh of the following sets are empty sets?

Solution