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Class 12 Relations And Functions · Assertion Reason1 Markstypes_of_functions

Class 12 Maths · Relations And Functions · Assertion Reason #115

Assertion: The function \(f:\mathbb R\to\mathbb R\), \(f(x)=x\), is one-one. Reason: A function \(g:A\to B\) is onto if for every \(b\in B\) there exists \(a\in A\) with \(g(a)=b\).

✅ Step-by-Step Solution

Final Answer: Option (B): Both A and R are true, but R is not the correct explanation of A.
  1. The identity function is injective since f(x)=f(y) implies x=y. The Reason is a true definition of surjectivity, which does not explain injectivity.

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