Let α be the constant term in the binomial expansion of (√ x -6/(x^(3/2)))^n, n ≤ 15. If the sum of the coefficients of the remaining terms in the…

Let $\displaystyle \alpha$ be the constant term in the binomial expansion of $\displaystyle \left(\sqrt{x}-\frac{6}{x^{\frac{3}{2}}}\right)^n, n \leq 15$. If the sum of the coefficients of the remaining terms in the expansion is $\displaystyle 649$ and the coefficient of $\displaystyle x^{-n}$ is $\displaystyle \lambda \alpha$, then $\displaystyle \lambda$ is equal to $\displaystyle \_\_\_\_$.