Same chapter3 marksDifficulty: Medium
Is the relation R = {(1, 1), (2, 2), (1, 2)} on the set {1, 2} reflexive, symmetric and transitive?
Relations and Functions
3 marksDifficulty: Medium
If f(x) = 2x + 3 and g(x) = (x − 3)/2, show that g is the inverse of f.
Original Khojo Papers practice question — not from a past board paper.
Answer
f(g(x)) = 2((x − 3)/2) + 3 = x and g(f(x)) = ((2x + 3) − 3)/2 = x, so g = f−1.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
A function and its inverse compose to the identity in both orders, which is the definition.
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