SOLUTION: Please help... how to find the constant term in the expansion of (3x- 1/(6x))^14 I got -429/16 somehow. But there should be a formula which I am not sure. Thank you.

You're perfectly correct. It is .

1) You have to use the formula for a specific term in a binomial expansion, along with pertinent info to determine the term number at which the Xs will cancel.

2) After finding the term number of the constant, use the term number and the formula for a specific term in a binomial expansion, again, to find the constant.

3) You should get the above: .

Try it!!