The Newton-Raphson iteration $x_{n+1} = \frac{1}{2}\left(x_n+\frac{R}{x_n}\right)$ can be used to compute the
The given expression can be rewritten as,
x_{n+1} = x_{n} - (x_{n}^{2} -R)/2x_{n}
therefore, it computes the square root R. answer (C) is correct.
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