Find the middle terms in the expansion `(3x-(x^3)/6)^7` .

Explanation

`(3-frac{x^{3}}{6})^{7}`


Here, `n` is an odd number.


Therefore, the middle terms are `(frac{7+1}{2})` th and `(frac{7+1}{2}+1)` th, i, e , 4th and 5th terms.


Now, we have
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