Chứng minh rằng C = A giao B

. Cho A={x∈N|x⋮6}A={x∈N|x⋮6}; B={x∈N|x⋮15}B={x∈N|x⋮15}; C={x∈N|x⋮30}C={x∈N|x⋮30}

CMR: C=A∩B