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**dunsta** A = {n ∈ Z|2 ≤ n ≤ 10}, for positive integer Am = {n ∈ A| n is divisible by m}

A = {2,3,4,5,6,7,8,9,10}

A1 = {2,3,4,5,6,7,8,9,10}

A2 = {2,4,6,8,10}

A11 = {}

A2nA3 (n = intersection)

A2 = {2,4,6,8,10}

A3 = {3,6,9}

so A2nA3 = {6}

Cartesian product A3×A5×A7

A3 = {3,6,9}

A5 = {5,10}

A7 = {7}

So Cartesian product of A3×A5×A7 = {(3,5,7),(3,5),(3,10,7),(3,10),(6,5,7),(6,5),(6,10 ,7),(6,10),(9,5,7),(9,5),(9,10,7),(9,10)}

Powerset P(A3) = ({}, {3}, {6},{9}, {3,6},{3,9},{6,9},{3,6,9}

Is {A2,A3,A5,A7} a partition of set A? no, they are not disjoint, A2,A3 share element 6.

If B = (A-(A3 U A5 U A7)) are B, A3, A5,A7 a partition? yes, they are disjoint

Is {A3,A5,A7} a partition of A? yes they are disjoint.

Am I on the right track?

Thanks for any help :)