Question

( 3y -1/y ) ^5

Answer 1

\[(-1/y)^5 + 5 \times (-1/y)^4 \times 3y \]........ and so on. see if you can do the rest.

Answer 2

For more info on this subject you can look here:

http://en.wikipedia.org/wiki/Pascal's_triangle

Answer 3

http://www.krysstal.com/binomial.html This is better