While finding the roots of f(x)=x2−4=0 using Newton - Raphson method, initial value of (x, x1 = 1). If the value obtained after first iteration isx2.
The Newton-Raphson method uses an iterative process to approach one root of a function. The specific root that the process locates depends on the initial, arbitrarily chosen x-value.
xn+1=xn−f(xn)f′(xn)
Here, xn is the current known x-value, (f(xn)) represents the value of the function at xn, and f′(xn) is the derivative (slope) at xn.
xn+1 represents the next x-value that you are trying to find.
Here, we have f(x)=x2−2 and x1=1
f′(x)=2x ⇒f(x1)=f(1)=1−2=−1
f′(x1)=f′(1)=2
⇒x2=x1−f(x1)f′(x1)
=1−(−12)=1+0.5=1.5
Thus, the approximate root is 1.5.