If left(frac1^15C_0 + frac1^15C_1right) left(frac1^15C_1 + frac1^15C_2right) dots left(frac1^15C_12 + frac1^15C_13right) = fracalpha^13^14C_0 cdot ^14C_1 dots ^14C_12, then 30alpha is equal to ____.

Numerical Answer Type:
Enter a numerical value Answer: 32 to 32 +4 marks

Solution & Explanation

### Related Formula ^nC_r + ^nC_r+1 = ^n+1C_r+1 frac^n+1C_r+1n+1 = frac^nC_rr+1 ### Core Logic Simplify the general term of the product: T_r = frac1^15C_r + frac1^15C_r+1 = frac^15C_r+1 + ^15C_r^15C_r cdot ^15C_r+1 = frac^16C_r+1^15C_r cdot ^15C_r+1 ### Step 1: Simplify General Term Using the relation ^16C_r+1 = frac16r+1 ^15C_r: T_r = fracfrac16r+1 ^15C_r^15C_r cdot ^15C_r+1 = frac16(r+1) cdot ^15C_r+1 Also, (r+1) cdot ^15C_r+1 = 15 cdot ^14C_r. T_r = frac1615 cdot ^14C_r = frac16/15^14C_r ### Step 2: Take the Product We need the product from r = 0 to 12: prod_r=0^12 T_r = prod_r=0^12 frac16/15^14C_r = frac(16/15)^13prod_r=0^12 ^14C_r = fracleft(frac1615right)^13^14C_0 cdot ^14C_1 dots ^14C_12 ### Step 3: Evaluate alpha Comparing with the given RHS fracalpha^13textproduct: alpha = frac1615 Then 30alpha = 30 left( frac1615 right) = 32. ### Pattern Recognition Product series of binomial fractions usually collapse by pairing the sum into Pascal's identity, separating the n coefficient and canceling factorials vertically. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Maths: Binomial Theorem

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