Intermediate
Discrete Mathematics & Math
Q58 / 100
What is the handshaking lemma in graph theory?
Correct! Well done.
Incorrect.
The correct answer is B) The sum of all vertex degrees equals twice the number of edges: Σ deg(v) = 2|E|
B
Correct Answer
The sum of all vertex degrees equals twice the number of edges: Σ deg(v) = 2|E|
Explanation
Each edge contributes 2 to the degree sum (one to each endpoint). Corollary: the number of odd-degree vertices is always even. Fundamental for proving impossibility results (e.g., Königsberg bridges).
Progress
58/100