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+# Example 7     Chapter 6       Page no.: 147
+# Newton-Raphson Method
+
+install.packages("numDeriv")
+library("numDeriv")
+
+# Given Function
+u <- function(x) {
+  x^2-3*x+2
+}
+
+curve(u, xlim=c(-5,5), col='blue', lwd=2, lty=2, ylab='f(x)')
+abline(h=0)
+abline(v=0)
+
+# From the curve the points in the vicinity are noted
+a <- 0
+b <-1
+
+newton.raphson <- function(f, a, b, tol = 1e-5, n = 1000) {
+  require(numDeriv) # Package for computing f'(x)
+  
+  x0 <- a # Set start value to supplied lower bound
+  k <- n # Initialize for iteration results
+  
+  # Check the upper and lower bounds to see if approximations result in 0
+  fa <- f(a)
+  if (fa == 0.0) {
+    return(a)
+  }
+  
+  fb <- f(b)
+  if (fb == 0.0) {
+    return(b)
+  }
+  
+  for (i in 1:n) {
+    dx <- genD(func = f, x = x0)$D[1] # First-order derivative f'(x0)
+    x1 <- x0 - (f(x0) / dx)
+    k[i] <- x1 
+    # Checking difference between values
+    if (abs(x1 - x0) < tol) {
+      root.approx <- tail(k, n=1)
+      res <- list('root approximation' = root.approx, 'iterations' = k)
+      return(res)
+    }
+    # If Newton-Raphson has not yet reached convergence set x1 as x0 and continue
+    x0 <- x1
+  }
+  print('Too many iterations in method')
+}
+
+N <- newton.raphson(u, a, b)
+cat("The root closer to the point x=0 is",N)
+\ No newline at end of file