"Given ( f(x) = x^2 - a ), show that the Newton-Raphson iteration reduces to ( x_n+1 = \frac12(x_n + \fracax_n) ), and hence explain why the method fails if ( x_0 = 0 )."

Numerical Methods Madasmaths

"Given ( f(x) = x^2 - a ), show that the Newton-Raphson iteration reduces to ( x_n+1 = \frac12(x_n + \fracax_n) ), and hence explain why the method fails if ( x_0 = 0 )."