Q.2 If sum_(k=10)^(2006)kC10) simplifies to ^(n)C_(p) where p is prime...
Given:
The sum of the binomial coefficients from k = 10 to k = 2006 is given by:
∑(k=10)^(2006)kC10
To find:
The value of (n p) where p is prime.
Solution:
Step 1: Simplifying the given expression
We know that the binomial coefficient nCr can be expressed as nC(r-1) * (n-r+1) / r.
Using this property, we can simplify the given sum as follows:
∑(k=10)^(2006)kC10 = ∑(k=10)^(2006)(kC9 * (k+1) / 10)
Now, let's split the sum into two parts:
Part 1: ∑(k=10)^(2006)kC9
Part 2: ∑(k=10)^(2006)(k+1) / 10
Step 2: Evaluating Part 1
Using the same property as above, we can further simplify Part 1:
∑(k=10)^(2006)kC9 = ∑(k=10)^(2006)(kC8 * (k+1) / 9)
Continuing this process, we can simplify Part 1 as:
∑(k=10)^(2006)kC9 = ∑(k=10)^(2006)(kC0 * (k+1) / 9)
Since kC0 = 1 for all values of k, we can rewrite Part 1 as:
Part 1 = ∑(k=10)^(2006)(k+1) / 9
Step 3: Evaluating Part 2
Using the property of arithmetic series, we can evaluate Part 2 as follows:
Part 2 = ((2006+1) + 10) * ((2006-10+1) / 2) / 10
= (2007 + 10) * (1997 / 2) / 10
= 10017
Step 4: Evaluating the final expression
Now, substituting the values of Part 1 and Part 2 into the original expression:
∑(k=10)^(2006)kC10 = Part 1 * Part 2
= (∑(k=10)^(2006)(k+1) / 9) * 10017
Step 5: Determining the value of (n p)
From the simplified expression above, we can see that the value of (n p) will be equal to the coefficient of n in the final expression. In this case, the coefficient of n is 1.
Therefore, the value of (n p) is 1.
Final Answer: The value of (n p) is 1. Therefore, the correct option is (1) 2017.