SOLUTION: HELP! What is the fourth term in the expansion. (2z-3)^5

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Question 890403: HELP! What is the fourth term in the expansion. (2z-3)^5
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
The formula is easier to remember this way:

If you start counting with zero instead of with 1, the Rth term of

(A+B)N is

C(N,R)AN-RBR

The 4th term if you count starting with with 1, is the 3rd term 
if you count starting with zero.

(2z-3)5

C(5,3)(2z)5-3(-3)3 =

10(2z)2(-27) =

-270(22z2) =

-270(4z4) =

-1080z2

Edwin