diff --git a/README.md b/README.md
index 1de772f..73ee1a7 100644
--- a/README.md
+++ b/README.md
@@ -44,3 +44,15 @@ df = @(x) -(2*(x)^2-4*x+1)*exp(-(x-1)^2);
 | 4 | 3 |   4.9605  |
 | 5 | 3 |   4.3873  |
 ```
+```matlab
+### convergence of Newton-Raphson method
+
+| iteration | x_i | approx error |
+| --- | --- | --- |
+| 0 |  1.2 |     n/a       |
+| 1 |  1.2 |   22.1239     |
+| 2 |  1.2 |    1.7402     |
+| 3 |  1.2 |    0.0011     |
+| 4 |  1.2 |    2.3315e-13 |
+| 5 |  1.2 |    2.3315e-13 |
+```
diff --git a/newtraph_f.m b/newtraph_f.m
index fee1ee3..a2a83a7 100644
--- a/newtraph_f.m
+++ b/newtraph_f.m
@@ -1,3 +1,3 @@
 f = @(x) (x-1)*exp(-(x-1)^2);
 df = @(x) -(2*(x)^2-4*x+1)*exp(-(x-1)^2);
-[root,ea,iter]=newtraph(f,df,3,.00001,5)
\ No newline at end of file
+[root,ea,iter]=newtraph(f,df,1.2,.00001,5)
\ No newline at end of file