1.Find n, if the term 11 coefficient it is 6 time the term 10 coefficient in
2.(6x^7 + 5x^(-4))^n
I am not sure what term 11 and 10 are (counted from what?), but you should not have all those powers of x in your calculation. The coefficient is the value in front of xwhatever.
81 looks right to me.
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