For , \(\Big(2x^2-\frac{1}{x}\Big)^{20}\)
a = 2x2 , b = \(\frac{-1}{x}\) and n=20
We have a formula,
To get coefficient of x9 we must have,
(x)40-3r = (x)9
• 40 - 3r = 9
• 3r = 31
• r = 10.3333
As (20r) = (2010.3333) is not possible
Therefore, the term containing x9 does not exist in the expansion of \(\Big(2x^2-\frac{1}{x}\Big)^{20}\)