## Discussion Forum

Que. | Consider the following relations:
R1(a,b) iff (a+b) is even over the set of integers R2(a,b) iff (a+b) is odd over the set of integers R3(a,b) iff a.b > 0 over the set of non-zero rational numbers R4(a,b) iff |a - b| <= 2 over the set of natural numbers Which of the following statements is correct? |

a. | R1 and R2 are equivalence relations, R3 and R4 are not |

b. | R1 and R3 are equivalence relations, R2 and R4 are not |

c. | R1 and R4 are equivalence relations, R2 and R3 are not |

d. | R1, R2, R3 and R4 are all equivalence relations |

Answer:R1 and R3 are equivalence relations, R2 and R4 are not |