definition: The Newton-Raphson method (also known as Newton's method) is a way to quickly find a good approximation for the root of a real-valued function f(x)=0. It uses the idea that acontinuous and differentiable function can be approximated by a straight line tangent to it. We Know, eq. of tangent is : y-y1 = f'(x) (x-x1). Y-f(Xo) = f'(xo)(X-Xo) 0-f(Xo) = f'(Xo)(X1-Xo); (putting y = 0) => X1 = Xo- (f(Xo)/f'(Xo)) Hence, Xn+1= Xn-(f(Xn)/f'(Xn)