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JEE MainMathematicsModerateRelation

The relation R defined on the set N of natural number by
x Ry⇔2x2−3xy+y2=0x\ Ry \Leftrightarrow 2x^{2} - 3xy + y^{2} = 0 is

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(i)
xRx⇔2x2−3x⋅x+x2=0∀x∈NxRx \Leftrightarrow 2x^{2} - 3x \cdot x + x^{2} = 0\forall x \in \mathbb{N}
R is reflexive.

(ii) for x=1, y=2

2x2−3xy+y2=2×1−3×1×2+4=2−6+4=02x^{2} - 3xy + y^{2} = 2 \times 1 - 3 \times 1 \times 2 + 4 = 2 - 6 + 4 = 0
But for y=1, x=2

2x2−3xy+y2=2x(2)2−3×1×2+(1)2=8−6+1=3≠02x^{2} - 3xy + y^{2} = 2x(2)^{2} - 3 \times 1 \times 2 + (1)^{2} = 8 - 6 + 1 = 3 \neq 0
So 1 R 2 but 2 not R 1

So R is not symmetric.

Source: Grass-G / M-17 Mathematics Paper 26 Nov Second.docx

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