The relation `' R '` in `NxxN` such that `(a ,\ b)\ R\ (c ,\ d)hArra+d=b+c` is reflexive but not symmetric reflexive and transitive but not symmetric an equivalence relation (d) none of these

Answer

c) an equivalence relation

Explanation

`forall a, b in N`, `(a,b)R(a,b)` as `a+b=b+a.`

Thus `forall a,b in N times N` is related to itself,

So ,R is also reflexive.


If `(a, b) R(c, d)` then` (c, d) R(a, b)` as if `(a+d=b+c)` then` (b+d=a+c).`

`therefore` R is symmetric.




For some `a, b, c, d, e, f in N`, if `(a, b) R(c, d)` and` (c,d)R(e,f)`

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