Let $K$ be the sum of the coefficients of the odd powers of $x$ in the expansion of $(1+ x )^{99}$. Let a be the middle term in the expansion of $\left(2+\frac{1}{\sqrt{2}}\right)^{200}$. If $\frac{{ }^{200} C _{99} K }{ a }=\frac{2^{\ell} m }{ n }$, where $m$ and $n$ are odd numbers, then the ordered pair $(l, n )$ is equal to :
$(50,51)$
$(51,99)$
$(50,101)$
$(51,101)$
If the sum of the coefficients in the expansion of ${(x - 2y + 3z)^n}$ is $128$ then the greatest coefficient in the expansion of ${(1 + x)^n}$ is
The sum of last eight consecutive coefficients in the expansion of $(1+x)^{15}$ is
The sum of all the coefficients in the binomial expansion of ${({x^2} + x - 3)^{319}}$ is
The coefficent of $x^7$ in the expansion of ${\left( {1 - x - {x^2} + {x^3}} \right)^6}$ is
Let $\left( a + bx + cx ^2\right)^{10}=\sum \limits_{ i =0}^{20} p _{ i } x ^{ i }, a , b , c \in N$. If $p _1=20$ and $p _2=210$, then $2( a + b + c )$ is equal to