## Discussion Forum

Que. | Let A = { 1,2,3,4,…….∞ } and a binary operation ‘+’ is defined by a + b = ab ∀ a,b ∈ A. Which of the following is true ? |

a. | ( A, + ) is a semi group but not monoid |

b. | ( A, + ) is a monoid but not group |

c. | ( A, + ) is a group |

d. | ( A, + ) is not a semi group |

Answer:( A, + ) is a monoid but not group |