Question -
Answer -
Given:
(2x2 –1/x)
If x9 occursat the (r + 1)th term in the given expression.
Then, we have:
Tr+1 = nCr xn-r ar
For this term tocontain x9, we must have
40 – 3r = 9
3r = 40 – 9
3r = 31
r = 31/3
It is not possible,since r is not an integer.
Hence, there is noterm with x9 in the given expansion.