diff --git a/docs/install-machine.md b/docs/install-machine.md
index 1e8d59df64..d627f29f9f 100644
--- a/docs/install-machine.md
+++ b/docs/install-machine.md
@@ -63,9 +63,9 @@ as:
 
 To install the scripts, copy or link them into your `/etc/bash_completion.d` or
 `/usr/local/etc/bash_completion.d` directory. To enable the `docker-machine` shell
-prompt, add `$(__docker-machine-ps1)` to your `PS1` setting in `~/.bashrc`.
+prompt, add `$(__docker_machine_ps1)` to your `PS1` setting in `~/.bashrc`.
 
-    PS1='[\u@\h \W$(__docker-machine-ps1)]\$ '
+    PS1='[\u@\h \W$(__docker_machine_ps1)]\$ '
 
 You can find additional documentation in the comments at the
 [top of each script](https://github.com/docker/machine/tree/master/contrib/completion/bash).