मराठी

The sum of coefficients of the two middle terms in the expansion of (1 + x)2n–1 is equal to 2n–1Cn.

Advertisements
Advertisements

प्रश्न

The sum of coefficients of the two middle terms in the expansion of (1 + x)2n–1 is equal to 2n–1Cn

पर्याय

  • True

  • False

MCQ
चूक किंवा बरोबर
Advertisements

उत्तर

This statement is False.

Explanation:

The given expression is (1 + x)2n–1 

Number of terms = 2n – 1 + 1 = 2n  ....(Even)

∴ Middle terms are `(2"n")/2` th term and `((2"n")/2 + 1)^"th"` terms

= nth terms and (n + 1)th terms

Coefficient of nth term = 2n–1Cn–1

And he coefficient of (n + 1)th term = 2n–1Cn

Sum of the coefficients = `""(2n + 1)C_(n - 1) + ""^(2n - 1)C_n`

= `""^(2n - 1)C_(n - 1) + ""^(2n - 1)C_n`

= `""^(2n - 1 + 1)C_n`

= 2nCn 

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 8: Binomial Theorem - Exercise [पृष्ठ १४६]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
पाठ 8 Binomial Theorem
Exercise | Q 37 | पृष्ठ १४६

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

Find the coefficient of x5 in (x + 3)8


Find the coefficient of a5b7 in (a – 2b)12


Write the general term in the expansion of (x2 – y)6


Write the general term in the expansion of (x2 – yx)12x ≠ 0


Find the 4th term in the expansion of (x – 2y)12 .


Find the middle terms in the expansions of `(x/3 + 9y)^10`


Find the middle term in the expansion of: 

(iii) \[\left( x^2 - \frac{2}{x} \right)^{10}\]

 


Find the middle term in the expansion of: 

(iv)  \[\left( \frac{x}{a} - \frac{a}{x} \right)^{10}\]

 


Find the middle terms in the expansion of: 

(iii) \[\left( 3x - \frac{2}{x^2} \right)^{15}\]

 


Find the middle terms in the expansion of:

(iv)  \[\left( x^4 - \frac{1}{x^3} \right)^{11}\]

 


Find the middle terms(s) in the expansion of:

(iv)  \[\left( 2x - \frac{x^2}{4} \right)^9\]


Find the middle terms(s) in the expansion of: 

(vii) \[\left( 3 - \frac{x^3}{6} \right)^7\]

  


Find the middle terms(s) in the expansion of:

(ix)  \[\left( \frac{p}{x} + \frac{x}{p} \right)^9\]

 


Find the term independent of x in the expansion of the expression: 

(i) \[\left( \frac{3}{2} x^2 - \frac{1}{3x} \right)^9\]

 


Find the term independent of x in the expansion of the expression: 

(ix) \[\left( \sqrt[3]{x} + \frac{1}{2 \sqrt[3]{x}} \right)^{18} , x > 0\]

 


If the coefficients of \[\left( 2r + 4 \right)\text{ th and } \left( r - 2 \right)\] th terms in the expansion of  \[\left( 1 + x \right)^{18}\]  are equal, find r.

 
 
 

Prove that the coefficient of (r + 1)th term in the expansion of (1 + x)n + 1 is equal to the sum of the coefficients of rth and (r + 1)th terms in the expansion of (1 + x)n.


If a, b, c and d in any binomial expansion be the 6th, 7th, 8th and 9th terms respectively, then prove that \[\frac{b^2 - ac}{c^2 - bd} = \frac{4a}{3c}\].


If the 2nd, 3rd and 4th terms in the expansion of (x + a)n are 240, 720 and 1080 respectively, find xan.


Find a, b and n in the expansion of (a + b)n, if the first three terms in the expansion are 729, 7290 and 30375 respectively.


If the term free from x in the expansion of  \[\left( \sqrt{x} - \frac{k}{x^2} \right)^{10}\]  is 405, find the value of k.

 
 

Find the sum of the coefficients of two middle terms in the binomial expansion of  \[\left( 1 + x \right)^{2n - 1}\]

 

Write the total number of terms in the expansion of  \[\left( x + a \right)^{100} + \left( x - a \right)^{100}\] .

 

In the expansion of \[\left( x^2 - \frac{1}{3x} \right)^9\] , the term without x is equal to

 

If rth term is the middle term in the expansion of \[\left( x^2 - \frac{1}{2x} \right)^{20}\]  then \[\left( r + 3 \right)^{th}\]  term is

 

 

Find numerically the greatest term in the expansion of (2 + 3x)9, where x = `3/2`.


The ratio of the coefficient of x15 to the term independent of x in `x^2 + 2^15/x` is ______.


Find the middle term (terms) in the expansion of `(x/a - a/x)^10`


Find the value of r, if the coefficients of (2r + 4)th and (r – 2)th terms in the expansion of (1 + x)18 are equal.


Show that the middle term in the expansion of `(x - 1/x)^(2x)` is `(1 xx 3 xx 5 xx ... (2n - 1))/(n!) xx (-2)^n`


If the middle term of `(1/x + x sin x)^10` is equal to `7 7/8`, then value of x is ______.


The position of the term independent of x in the expansion of `(sqrt(x/3) + 3/(2x^2))^10` is ______.


The number of terms in the expansion of [(2x + y3)4]7 is 8.


If n is the number of irrational terms in the expansion of `(3^(1/4) + 5^(1/8))^60`, then (n – 1) is divisible by ______.


The sum of the co-efficients of all even degree terms in x in the expansion of `(x + sqrt(x^3 - 1))^6 + (x - sqrt(x^3 - 1))^6, (x > 1)` is equal to ______.


Let for the 9th term in the binomial expansion of (3 + 6x)n, in the increasing powers of 6x, to be the greatest for x = `3/2`, the least value of n is n0. If k is the ratio of the coefficient of x6 to the coefficient of x3, then k + n0 is equal to ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×