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 ".