diff --git a/docs/source/advanced/chain/create_image_for_runimage.rst b/docs/source/advanced/chain/create_image_for_runimage.rst
index fe029e1b0..a8d68339b 100644
--- a/docs/source/advanced/chain/create_image_for_runimage.rst
+++ b/docs/source/advanced/chain/create_image_for_runimage.rst
@@ -14,7 +14,7 @@ How to prepare a image for ``runimage`` in ``chain``
     * go to the directory and run `tar -zcvf <image> .`
 
 * Example
-    In the example, it shows how to install an independent pkg a.rpm 
+    In the example, it shows how to install an independent pkg a.rpm
 
     * Create the directory for the image: ::
 
@@ -29,7 +29,7 @@ How to prepare a image for ``runimage`` in ``chain``
 
          cat runme.sh
          echo "start installing a.rpm"
-         rpm -ivh a.rpm  
+         rpm -ivh a.rpm
 
     * modify the runme.sh script permission: ::