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Find the coefficient of `x^(20)`in `(x^2+2+1/(x^2))^(-5)(1+x^2)^(40)dot` |
Answer» Given expansion is `E = ((x+(1)/(x))^(2))^(-5) (1+x^(2))^(40)` `= ((x^(2) + 1)/(x))^(-10) (1+x^(2))^(40) = x^(10)(1+x^(2))^(30)` Coefficient of `x^(20)` in E = Coefficient of `x^(10)` in `(1+x^(2))^(30)` `= .^(30)C_(5)` |
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