If A= ( array lll a₁ & b₁ & c₁ a₂ & b₂ & c₂ a₃ & b₃ & c₃ array ): a_i, b_i, c_i,(i=1,2,3) . are the . array l binomial coefficients in the expansion of (1+ x )¹¹ then the number of elements in set A is array ,

Step-by-step solution

(1+ x ¹¹ )= ¹¹ C ₀ x ^0+ ¹¹ C ₁ x ^1+ ¹¹ C ₂ x ^2+ ¹¹ C ₃ x ^3+ ¹¹ C ₄ x ^4+ ¹¹ C ₅ x ^5+ ¹¹ C ₆ x ^6+ ¹¹ C ₇ x ^7+ ¹¹ C ₈ x ^8+ ¹¹ C ₉ x ^9+ ¹¹ C ₁₀ x ¹⁰+ ¹¹ C ₁₁ x ¹¹ ¹¹ C ₀= ¹¹ C ₁₁, ¹¹ C ₁= ¹¹ C ₁₀, ¹¹ C ₂= ¹¹ C ₉, ¹¹ C ₃= ¹¹ C ₈, ¹¹ C ₄= ¹¹ C ₇, ¹¹ C ₅= ¹¹ C ₆ So, In the expansion of (1+x^ Y 1 ) , there are 6 different coefficients. a _ i , b _ i , c _ i ( i =1,2,3) has 6 choices. No. of elements in the set A=6^9 ,