Miscellaneous

Let A = {– 1, 0, 1, 2}, B = {– 4, – 2, 0, 2} and f, g : A → B be functions defined by f(x) = x2 – x, x ∈ A and g(x) = 2|x – ½| – 1, x ∈ A. Are f and g equal? Justify your answer. (Hint: One may note that two functions f : A → B and g : A → B such that f(a) = g (a) ∀ a ∈ A, are called equal functions).

solution: Given capacities are: f(x) = x2 – x and g(x) = 2|x – ½| - 1 At x = - 1 f(- 1) = 12 + 1 = 2 and g(- 1) = 2|-1 – ½| - 1 = 2 At x = 0 F(0) = 0 and g(0) = 0 At x = 1 F(1) = 0 and g(1) = 0 At x...

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Define a binary operation * on the set {0, 1, 2, 3, 4, 5} as a * b = {   ???? + ????        ???????? ???? + ???? < ???? ???? + ???? − ????      ???????? ???? + ???? ≥ ???? . Show that zero is the identity for this operation and each element a ≠ 0 of the set is invertible with 6 – a being the inverse of a.

Arrangement: Let x = {0, 1, 2, 3, 4, 5} and activity * is characterized as a * b = { ???? + ???? ???????? ???? + ???? < 6 ???? + ???? − 6 ???????? ???? + ???? ≥ 0 Let us say, is the personality...

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Given a non-empty set X, let * : P(X) × P(X) → P(X) be defined as A * B = (A – B) ∪ (B – A), ∀ A, B ∈ P(X). Show that the empty set ϕ is the identity for the operation * and all the elements A of P(X) are invertible with A–1 = A. (Hint : (A – ϕ) ∪ (ϕ– A) = A and (A – A) ∪ (A – A) = A * A = ϕ).

solution: x ∈ P(x) Furthermore, ϕ is the character component for the activity * on P(x). Additionally A*A= = Each component An of P(X) is invertible with A-1 = A.

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Consider the binary operations * : R × R → R and o : R × R → R defined as a * b = |a– b| and a o b =a, ∀ a, b ∈ R. Show that ∗ is commutative but not associative, o is associative but not commutative. Further, show that ∀ a, b, c ∈ R, a * (b o c) = (a * b) o (a* c). [If it is so, we say that the operation * distributes over the operation o]. Does o distribute over *? Justify your answer.

Solution: Stage 1: Check for commutative and cooperative for activity *. a * b = |a – b| and b * a = |b – a| = (a, b) Activity * is commutative. a(bc) = a|b-c| = |a-(b-c)| = |a-b+c| and (ab)c =...

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Given a non-empty set X, consider the binary operation * : P(X) × P(X) → P(X) given by A * B = A ∩ B ∀ A, B in P(X), where P(X) is the power set of X. Show that X is the identity element for this operation and X is the only invertible element in P(X) with respect to the operation * .

Solution: Leave T alone a non-void set and P(T) be its force set. Let any two subsets An and B of T. A ∪ B ⊂ T Along these lines, A ∪ B ∈ P(T) Thusly, ∪ is a twofold procedure on P(T). Additionally,...

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