question_answer

Let \[f(x)=\underset{n\to \infty }{\mathop{\lim }}\,\frac{{{x}^{2n}}-1}{{{x}^{2n}}+1},then\]

A) \[f(x)=1,for|X|\,\,\,>1\]                   

B) \[f(x)=-2,for|X|\,\,\,<1\]

C)  f (x) is not defined for any value of x  

D)  \[f(x)=1,for|X|=1\]