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ASSERTION (A): The relation f : {1, 2, 3, 4} → {x, y, z, p} defined by f = {(1, x), (2, y), (3, z)} is a bijective function. REASON (R): The function f : {1, 2, 3} → {x, y, z, p} - Mathematics

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Question

ASSERTION (A): The relation f : {1, 2, 3, 4} `rightarrow` {x, y, z, p} defined by f = {(1, x), (2, y), (3, z)} is a bijective function.

REASON (R): The function f : {1, 2, 3} `rightarrow` {x, y, z, p} such that f = {(1, x), (2, y), (3, z)} is one-one.

Options

  • Both (A) and (R) are true and (R) is the correct explanation of (A).

  • Both (A) and (R) are true but (R) is not the correct explanation of (A).

  • (A) is true but (R) is false.

  • (A) is false but (R) is true.

MCQ

Solution

(A) is false but (R) is true.

Explanation:

Assertion is false. As element 4 has no image under f, so relation f is not a function.

Reason is true. The given function f : {1, 2, 3} `rightarrow` {x, y, z, p} is one – one, as for each a ∈ {1, 2, 3}, there is different image in {x, y, z, p} under f.

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