Not able to use roscd command as it gives error

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I get the following error when I use roscd:

Inspiron-5559:~$ roscd beginner_tutorials
roscd: No such package/stack 'beginner_tutorials'

But everytime when I source the setup.bash file then it works:

Inspiron-5559:~/catkin_ws$ . ~/catkin_ws/devel/setup.bash
Inspiron-5559:~/catkin_ws$ source devel/setup.bash

Then

Inspiron-5559:~/catkin_ws$ roscd beginner_tutorials
Inspiron-5559:~/catkin_ws/src/beginner_tutorials$

Hence I need to source the file everytime for roscd to work..How do I remove this error?