हिंदी

Find the term independent of x, x ≠ 0, in the expansion of (3x22-13x)15

Advertisements
Advertisements

प्रश्न

Find the term independent of x, x ≠ 0, in the expansion of `((3x^2)/2 - 1/(3x))^15`

योग
Advertisements

उत्तर

General Term `"T"_(r + 1) = ""^n"C"_r x^(n - r) y^r`

= `""^15"C"_r ((3x^2)/2)^(15 - r)  (- 1/(3x))^r`

= `""^15"C"_r (3/2)^(15 - r) * (x)^(30 - 2r) * (- 1/3)^r * 1/x^r`

= `""^15"C"_r (3/2)^(15 - r) * (x)^(30 - 2r - r) (-1)^r * 1/(3)^r`

= `""^15"C"_r (3/2)^(15 - r) * x^(30 - 3r) (-1)^r * 1/(3)^r`

For getting the term independent of x

30 – 3r = 0

⇒ r = 10

On putting the value of r in the above expression, we get

= `""^15"C"_10 (3/2)^(15 - 10) (-1)^10 * 1/(3)^10`

= `""^15"C"_10  (3)^5/(2)^5 * 1/(3)^10`

= `""^15"C"_10 * 1/((2)^5 * (3)^5)`

= `""^15"C"_10 (1/6)^5`

Hence, the required term = `""^15"C"_10 (1/16)^5`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Binomial Theorem - Exercise [पृष्ठ १४२]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
अध्याय 8 Binomial Theorem
Exercise | Q 1 | पृष्ठ १४२

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

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


The coefficients of the (r – 1)th, rth and (r + 1)th terms in the expansion of (x + 1)n are in the ratio 1:3:5. Find n and r.


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

(i) \[\left( x - \frac{1}{x} \right)^{10}\]

 


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

(ii)  \[\left( 1 - 2x + x^2 \right)^n\]


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

(v) \[\left( x - \frac{1}{x} \right)^{2n + 1}\]

 


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

(vi)  \[\left( \frac{x}{3} + 9y \right)^{10}\]

 


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: 

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

 


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

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

 


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.


The coefficients of 5th, 6th and 7th terms in the expansion of (1 + x)n are in A.P., find n.

 

If the coefficients of 2nd, 3rd and 4th terms in the expansion of (1 + x)n are in A.P., then find the value of n.


Find a, if the coefficients of x2 and x3 in the expansion of (3 + ax)9 are equal.

 

If in the expansion of (1 + x)n, the coefficients of three consecutive terms are 56, 70 and 56, then find n and the position of the terms of these coefficients.


If 3rd, 4th 5th and 6th terms in the expansion of (x + a)n be respectively a, b, c and d, prove that `(b^2 - ac)/(c^2 - bd) = (5a)/(3c)`.


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.


Write the middle term in the expansion of  \[\left( x + \frac{1}{x} \right)^{10}\]

 

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

 

If in the expansion of (a + b)n and (a + b)n + 3, the ratio of the coefficients of second and third terms, and third and fourth terms respectively are equal, then n is


If A and B are the sums of odd and even terms respectively in the expansion of (x + a)n, then (x + a)2n − (x − a)2n is equal to


The number of irrational terms in the expansion of \[\left( 4^{1/5} + 7^{1/10} \right)^{45}\]  is

 

In the expansion of \[\left( \frac{1}{2} x^{1/3} + x^{- 1/5} \right)^8\] , the term independent of x is

 

The total number of terms in the expansion of \[\left( x + a \right)^{100} + \left( x - a \right)^{100}\]  after simplification is

 

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 the middle term (terms) in the expansion of `(p/x + x/p)^9`.


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 term independent of x in the expansion of (1 + x + 2x3) `(3/2 x^2 - 1/(3x))^9`


In the expansion of `(x^2 - 1/x^2)^16`, the value of constant term is ______.


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


The last two digits of the numbers 3400 are 01.


If the expansion of `(x - 1/x^2)^(2n)` contains a term independent of x, then n is a multiple of 2.


The number of rational terms in the binomial expansion of `(4^(1/4) + 5^(1/6))^120` is ______.


Let the coefficients of the middle terms in the expansion of `(1/sqrt(6) + βx)^4, (1 - 3βx)^2` and `(1 - β/2x)^6, β > 0`, common difference of this A.P., then `50 - (2d)/β^2` is equal to ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×