Recent content by leilei

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    Solving 3-1 Trees: Proving Even # of Vertices & Finding Leaf #s

    please help solve tree problem... A tree is called a 3-1 tree if every vertex in the tress has degree equal to either 3 or 1. 1. Draw all 3-1 trees with four or fewer vertices of degree 3. 2. Prove that a 3-1 tree must have an even number of vertices. 3. Find a formula for the number of...
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    Undergrad Discrete math venn diagram proof

    this proof is to show why the two pictures/diagram are the same...
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    Undergrad Discrete math venn diagram proof

    Prove for all sets A,B, and C : A complement UNION B complement = (A intercept B) complement help me out here please
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    Graduate Prove that if and [j] are equivalence classes modulo

    Prove that if [i] and [j] are equivalence classes modulo 1. Prove that if [i] and [j] are equivalence classes modulo n such that [i]=[j], then gcd(i,n)=gcd(j,n) 2. Prove that if gcd(a,b)=1 and if c divides b, then gcd(a,c)=1. please help
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    Undergrad Proof of Venn Diagram for Sets A, B & C

    Proof for all sets A, B, and C: A complement U B complement = (A Intercept B) complement. can someone help??
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    Undergrad What is the relationship between subspaces V and W if V is contained in W?

    subspaces and dimension! Consider two subspaces V and W of R^n ,where V is contained in W. Why is dim(V)<= dim(W)...? "<=" less than or equal to
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    Undergrad Proving Subsets: A Venn Diagram Approach

    Thanks a lot !
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    Undergrad Proving Subsets: A Venn Diagram Approach

    Proof subset? Given three sets A, B, and C, set X = (A-B) U (B-C) U (C-A) and Y = (A∩B∩C) complement C. Prove that X is subset of Y. Is Y necessarily a subset of X? If yes, prove it. If no, why? ---When I draw the two venn diagrams X and Y, they are the same, but I don't know how to prove...