A function fff is defined by f(x)=limn→∞xn+1xn−1f(x) = \lim_{n \to \infty} \frac{x^n + 1}{x^n - 1}f(x)=limn→∞xn−1xn+1. Find the derivative of f(x)f(x)f(x) for ∣x∣>1|x| > 1∣x∣>1.
000
111
−1-1−1
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