Se da multimea A = {1,2,3,4,5,6,7}. Determinati numarul submultiplilor de doua elemente ale multimii A, astfel incat suma elementelor fiecareia sa fie un nr. par.
.Se dau multimile A = {x|x = 5n + 7, n ∈ N} si B = {y|y =  n^{2} , n ∈ N}. Determinati elementele multimilor C= { x ∈ A| x < 30} si D ={ y ∈ B| 30 < y < 100 }

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Răspunsuri

2014-08-29T16:57:15+03:00
1)Submultimile sunt:
{1,3},{1,5},{1,7},
{2,4},{2,6},
{3,5},{3,7},
{4,6},
{5,7}.
In concluzie sunt 9 submultimi.

2)Elementele multimii A sunt:
5*0+7=7
5*1+7=12
5*2+7=17
5*3+7=22
5*4+7=27
5*5+7=32
....
Multimea C={7,12,17,22,27}


Elementele multimii B sunt:
0^2=0\\&#10;1^2=1\\&#10;2^2=4\\&#10;3^2=9\\&#10;4^2=16\\&#10;5^2=25\\&#10;6^2=36\\&#10;7^2=49\\&#10;8^2=64\\&#10;9^2=81\\&#10;10^2=100\\&#10;11^2=121\\&#10;....
Multimea D={36,49,64,81}

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