Deepak Kumar you can find the solution in the following figure!!!This link may help you also for other problems (Solution in page 11)
http://aries.ucsd.edu/NAJMABADI/CLASS/ECE65/12-W/NOTES/Amp-2.pdf 

[![enter image description here][1]][1]


  [1]: https://i.sstatic.net/vJeGP.png