Dear srinath

This shows that your basic concept are not clear.

for comples number,permutation and combination and binomial theorem you should refer Hall and knight,

at the same time you should also refer your class notes and study material provided in your class.

i think complex number is well explined in hall and knight ,you will feel comfortable after solving this book

Please feel free to post as many doubts on our discussion forum as you can.
If you find any question Difficult to understand - post it here and we will get you
the answer and detailed  solution very  quickly.

 We are all IITians and here to help you in your IIT JEE preparation.

All the best.
 
Regards,
Askiitians Experts
Badiuddin