Binomial Theore...

In the expansion of $$\left( 1+x \right) ^{ n }$$, The binomial coefficients of three consecutive terms are respectively 220, 495 and 795, the value 

The term independent of x in the expansion of  $$\displaystyle \left ( x -\dfrac{1}{4} \right )^4\left ( x + \dfrac{1}{x} \right )^3$$

If in the expansion of $$(1+x)^{20}$$,the coefficients of rth and (r+4)th terms are equal,then r is equal to

If $$(1+2x+3x^2 )^{10} = a_0+a_1x+a_2x^2+\ ...\,+a_{20}x^{20}$$, then $$a_1$$ equals

Let $$2.^{20}C_0 + 5. ^{20} C_1 + 8. ^{20}C_2 + ..... + 62. ^{20}C_{20}$$. then sum of this series is 

Find the $$7^{th}$$ term from the end in the expansion of $$\left(2x^{2}-\dfrac{3}{2x}\right)^{8}$$

Find the coefficient of $$x^{10}$$ in the expansion of $$\left(2x^{2}-\dfrac{1}{x}\right)^{20}$$

The greatest term in the expansion of $$(2x + 3y)^{11}$$ when x = 9 and y = 4 is :

Find the coefficient of $$x^{-15}$$ in the expansion of $$\left(3x^{2}-\dfrac{a}{3x^{3}}\right)^{10}$$

If $$p$$ is a real number and if the middle term in the expansion of $$\left(\dfrac{p}{2}+2\right)^{8}$$ is $$1120$$, find $$p$$