Suppose f is defined from R→[−1,1] as f(x)=x2−1x2−1 where R is the set of real number. Then statement which does not hold is
A function f:(R−A)→R is defined as f(x)=x+2x2−3x+4, where R is one set of real numbers and A is a finite set of points where f(x) is not defined. Then n(A)=___.