$\sum\limits_{k = 0}^{10} {^{20}{C_k} = } $
${2^{19}} + \frac{1}{2}{\,^{20}}{C_{10}}$
${2^{19}}$
$^{20}{C_{10}}$
એકપણ નહિ.
$\left( {\begin{array}{*{20}{c}}n\\0\end{array}} \right) + 2\,\left( {\begin{array}{*{20}{c}}n\\1\end{array}} \right) + {2^2}\left( {\begin{array}{*{20}{c}}n\\2\end{array}} \right) + ..... + {2^n}\left( {\begin{array}{*{20}{c}}n\\n\end{array}} \right)=$ . . .
$\left( {\begin{array}{*{20}{c}}{20}\\0\end{array}} \right) - \left( {\begin{array}{*{20}{c}}{20}\\1\end{array}} \right)$$+$$\left( {\begin{array}{*{20}{c}}{20}\\2\end{array}} \right) - \left( {\begin{array}{*{20}{c}}{20}\\3\end{array}} \right)$$+…..-……+$$\left( {\begin{array}{*{20}{c}}{20}\\{10}\end{array}} \right)$ નો સરવાળો.
જો ${(1 + x)^n} = {C_0} + {C_1}x + {C_2}{x^2} + ... + {C_n}{x^n}$, તો ${C_0} + {C_2} + {C_4} + {C_6} + .....$ = . . .
$(1+x)^{15}$ ના વિસ્તરણમાં છેલ્લા આઠ ક્રમિક પદોના સહગુણકનો સરવાળો મેળવો