推 zolaism:請問是小黑大大嗎 12/30 10:41
Let X denote the set of sequences with finite domain.
Define a relation R on X as s R t if |domain s| = |domain t| and, if the
domain of s is {m, m + 1, . . . , m + k} and the domain of t is
{n, n + 1, . . . , n + k}, s(m+i) = t(n+i) for i = 0, . . . ,k.
(a) Show that R is an equivalence relation.
(b) Explain in words what it means for two sequences in X to be equivalent
under the relation R.
(c) Since a sequence is a function, a sequence is a set of ordered pairs.
Two sequences are equal if the two sets of ordered pairs are equal.
Contrast the difference between two equivalent sequences in X and
two equal sequenves in X.
Let R be a relaton on a set X. Define
ρ(R) = R U {(x,x) | x 屬於 X}
↑聯集符號
σ(R) = R U R^(-1)
R^n = R。R。R。...。R (nR's)
τ(R) = U {R^n | n = 1,2,...}
我在(c)之後最後的那一小段看得霧煞煞
在這請求板上強大的神人有辦法幫我解釋最後那部分 還有(b) (c)兩小題嗎
因為課本的詳解寫得很簡陋很不清楚 我看完之後還是看不懂
然後最後一段那邊我完全不知道在尬麻= =....
跪求強大的離散大大
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