Find the 5th term from the end in the expansion of (3x−1x2)
Fifth term from the end is (11−5+1)=7th term from beginning T7=T6+1=(−1)rnC2xn−ryr
=(−1)610C6(3x)4(1x2)6
=10C6×34×x4x12=210×81x8=17010x8
Find the 5th term from the end in the expansion of (x-1/x)^2