I had /opt/apache-tomcat-7.0.27/webapps/myapp in my document root,i removed it and tried your suggestion and it worked out.I dont have any virtual hosts defined and only one web server redirecting at one tomcat.At first i tried it with /var/www/html in
document root,but i didnt work out,i had gone through many tutorials and in some of them they told to change document root to tomcat's web application path ,so i did that,but i was running of clues tried the proxy syntax in every possible way and finally this is how i got with your help:
ProxyPass / http://localhost:8080/myapp/
ProxyPassReverse / http://localhost:8080/myapp/
(i have changed my tomcat port again to default)
so i have made two changes :
1.taked out /opt/apache-tomcat-7.0.27/webapps/myapp from DocumentRoot and <Directory> parts and replaced them with default "/var/www/html" .
2.Added / at end of myapp: /myapp/
And dear Sir i really thank full to you for your replies and all the help you have given... Thank you so much....
(And the moral i learnt from this exp is that, one should think logically but not blindly follow the tutorials