1. The problem statement, all variables and given/known data Hello everybody, I have a problem dealing with complex circuits, especially those that have extra symbols (transistors, earth, V_in, V_out). Hopefully somebody can give me helping hand. Thanks a bunch. This is the link to the problem which is on page 11 (the first one): http://www.vcaa.vic.edu.au/vce/studies/physics/pastexams/2006/physics1w06.pdf I apologize for any inconvenience. I really do not know whether I can post a picture on this forum. So I think it's safe to post the link here. 2. Relevant equations 3. The attempt at a solution I have been trying to read from many websites about transistors but it seems that they do not help much (they go into very small details which are beyond my level and my textbook does not explain things very clear). I am a year 11 student so please help me with this, I have struggled with this for a week and now I really worry.