Home
Class 12
MATHS
The coefficient of the (2m+1)^("th") and...

The coefficient of the `(2m+1)^("th")` and `(4m+5)^("th")` terms in the expansion of `(1+x)^(100)` are equal, then the value of `(m)/(2)` is equal to

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of \( \frac{m}{2} \) given that the coefficients of the \( (2m + 1)^{th} \) and \( (4m + 5)^{th} \) terms in the expansion of \( (1 + x)^{100} \) are equal. ### Step-by-step Solution: 1. **Identify the General Term**: The general term \( T_r \) in the expansion of \( (1 + x)^{100} \) is given by: \[ T_r = \binom{100}{r} x^r \] where \( r \) is the term number starting from 0. 2. **Find the Coefficient of the \( (2m + 1)^{th} \) Term**: For the \( (2m + 1)^{th} \) term, we have: \[ r = 2m \] Thus, the coefficient is: \[ \text{Coefficient of } T_{2m} = \binom{100}{2m} \] 3. **Find the Coefficient of the \( (4m + 5)^{th} \) Term**: For the \( (4m + 5)^{th} \) term, we have: \[ r = 4m + 4 \] Thus, the coefficient is: \[ \text{Coefficient of } T_{4m + 4} = \binom{100}{4m + 4} \] 4. **Set the Coefficients Equal**: According to the problem, these coefficients are equal: \[ \binom{100}{2m} = \binom{100}{4m + 4} \] 5. **Apply the Property of Binomial Coefficients**: The equality of binomial coefficients gives us two cases: - Case 1: \( 2m = 4m + 4 \) - Case 2: \( 2m + (4m + 4) = 100 \) 6. **Solve Case 1**: From \( 2m = 4m + 4 \): \[ 2m - 4m = 4 \implies -2m = 4 \implies m = -2 \] (This value is not valid since \( m \) must be non-negative.) 7. **Solve Case 2**: From \( 2m + 4m + 4 = 100 \): \[ 6m + 4 = 100 \implies 6m = 96 \implies m = 16 \] 8. **Find \( \frac{m}{2} \)**: Now, we need to find \( \frac{m}{2} \): \[ \frac{m}{2} = \frac{16}{2} = 8 \] ### Final Answer: The value of \( \frac{m}{2} \) is \( 8 \).
Promotional Banner

Similar Questions

Explore conceptually related problems

If the coefficients of (2r+4)^("th") term and (3r+4)^("th") term in the expansion of (1+x)^(21) are equal, find r.

If 17^(th) and 18^(th) terms in the expension of (2+a)^(50) are equal ,then the value of a is :

If the coefficient of (3r)^(th) and (r + 2)^(th) terms in the expansion of (1 + x)^(2n) are equal then n =

If the coefficient of (2r + 4)^(th) term and (r - 2)^(th) term in the expansion of (1 + x)^18 are equal then find r.

If the coefficient of (2r+1) th and (r+2) th terms in the expansion of (1+x)^(43) are equal, then the value of r(r!=1) is

Find the 5th term in the expansion of (1+x^2)^12

The coefficients of (2r +1) th and (r+2) th terms in the expansions of (1 +x)^(43) are equal. Find the value of r .

If the coefficients of (2r + 1)th term and (r + 2)th term in the expansion of (1 + x)^(48) are equal,find r .

If the coefficients of (p+1) th and (P+3) th terms in the expansion of (1+x)^(2n) are equal then prove that n=p+1

If the coefficient of r^(th) and (r+4)^(th) terms are equal in the expansion of (1+x)^(20) , then the value of r will be