English

Expand the expression: (2x-x2)5 - Mathematics

Advertisements
Advertisements

Question

Expand the expression: `(2/x - x/2)^5`

Sum

Solution

By using Binomial Theorem, the expression `(2/x - x/2)^5` can be explained as

`(2/x - x/2)^5  =  ^5C_0 (2/x)^5 -  ^5C_1  (2/x)^4  (x/2)  +  ^5C_2  (2/x)^3  (x/2)^2`

- `""^5C_3  (2/x)^2  (x/2)^3  +  ^5C_4 (2/x) (x/2)^4  -  ^5C_5  (x/2)^5`

= `(32)/x^5  - 5 (16/(x^4)) (x/2)  + 10 (8/x^3) (x^2/4) - 10 (4/x^2) (x^3/8) +5 (2/x)(x^4/16) - x^5/32`

= `32/x^5  - 40/x^3  + 20/x  - 5x + 5/8 x^3  - x^5/32`

shaalaa.com
  Is there an error in this question or solution?
Chapter 8: Binomial Theorem - Exercise 8.1 [Page 166]

APPEARS IN

NCERT Mathematics [English] Class 11
Chapter 8 Binomial Theorem
Exercise 8.1 | Q 2 | Page 166

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Expand the expression: (1– 2x)5


Expand the expression (1– 2x)5


Expand the expression: (2x – 3)6


Expand the expression: `(x + 1/x)^6`


Using binomial theorem, evaluate f the following:

(101)4


Find (a + b)4 – (a – b)4. Hence, evaluate `(sqrt3 + sqrt2)^4 - (sqrt3 - sqrt2)^4`


Show that 9n+1 – 8n – 9 is divisible by 64, whenever n is a positive integer.


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


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


If a and b are distinct integers, prove that a – b is a factor of an – bn, whenever n is a positive integer.

[Hint: write an = (a – b + b)n and expand]


Find the value of `(a^2 + sqrt(a^2 - 1))^4 + (a^2 - sqrt(a^2 -1))^4`


Find an approximation of (0.99)5 using the first three terms of its expansion.


If n is a positive integer, prove that \[3^{3n} - 26n - 1\]  is divisible by 676.

 
 

Show that  \[2^{4n + 4} - 15n - 16\]  , where n ∈  \[\mathbb{N}\]  is divisible by 225.

 
  
  

Find the rth term in the expansion of `(x + 1/x)^(2r)`


Expand the following (1 – x + x2)4 


Find the 4th term from the end in the expansion of `(x^3/2 - 2/x^2)^9`


Evaluate: `(x^2 - sqrt(1 - x^2))^4 + (x^2 + sqrt(1 - x^2))^4`


Find the term independent of x in the expansion of `(sqrt(x)/sqrt(3) + sqrt(3)/(2x^2))^10`.


The coefficient of xp and xq (p and q are positive integers) in the expansion of (1 + x)p + q are ______.


Find the coefficient of x15 in the expansion of (x – x2)10.


Find the sixth term of the expansion `(y^(1/2) + x^(1/3))^"n"`, if the binomial coefficient of the third term from the end is 45.


In the expansion of (x + a)n if the sum of odd terms is denoted by O and the sum of even term by E. Then prove that 4OE = (x + a)2n – (x – a)2n 


The total number of terms in the expansion of (x + a)100 + (x – a)100 after simplification is ______.


Given the integers r > 1, n > 2, and coefficients of (3r)th and (r + 2)nd terms in the binomial expansion of (1 + x)2n are equal, then ______.


The coefficient of a–6b4 in the expansion of `(1/a - (2b)/3)^10` is ______.


Let the coefficients of x–1 and x–3 in the expansion of `(2x^(1/5) - 1/x^(1/5))^15`, x > 0, be m and n respectively. If r is a positive integer such that mn2 = 15Cr, 2r, then the value of r is equal to ______.


The sum of the last eight coefficients in the expansion of (1 + x)16 is equal to ______.


If the coefficients of (2r + 4)th, (r – 2)th terms in the expansion of (1 + x)18 are equal, then r is ______.


Let `(5 + 2sqrt(6))^n` = p + f where n∈N and p∈N and 0 < f < 1 then the value of f2 – f + pf – p is ______. 


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×