Question

What is the fourth term in the expansion of (3 – x)^5? Use Pascal's Triangle.

Answer 1

The triangle goes as follows:
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1
these are the coefficients of the expansion, and the coefficient farthest left is the 0th term then goes up by one every time to the right. The second coefficient to the left is the 1st term and tells you the exponent.

Answer 2

Thank you, that helps a lot :)

Answer 3

You're welcome :)