Greetings.

I am currently studying at university. Unfortunately due to illnes I was forced to skip one month and now I fear that I was left behind.

In today test we solved some matrices.

http://i56.tinypic.com/21azayp.jpg

http://i52.tinypic.com/bdm651.jpg

http://i53.tinypic.com/mjy3af.jpg

http://i54.tinypic.com/5be5nm.jpg

I would really appreciate any pointers about those topics.

Basically, I want to know what kind of rules do I need to learn to solve these problems. Also, if possible, can you show step by step solution of those problems or similar problems so I get some idea what they want me to do there.

Right now all my knowledge of matrices consist of multiplication , addition, subtraction and finding inverse.