KEAM 2013 Math Paper

We know that,
(i) A function f:X→Y is said to be one-one, if distinct elements of X have distinct images in Y.
f is one-one when f(x1)=f(x2)⇒x1=x2
(ii) A function f:X→Y is said to be onto, if every element in Y has atleast one pre-image in X. Thus, if f is onto, then for each y∈X∃ atleast one element x∈X such that y=f(x)
∴ Negative of the statement "f is one-one and onto" is
" f is not one-to-one and onto"
which hold the logical statement, " R or not Q ".