मराठी

If f(x) = x+34x−5,g(x)=3+5x4x−1 then verify that (fog)(x) = x.

Advertisements
Advertisements

प्रश्न

If f(x) = `(x+3)/(4x−5) , "g"(x) = (3+5x)/(4x−1)` then verify that `("fog") (x)` = x.

बेरीज
Advertisements

उत्तर

f(x) = `(x+3)/(4x−5) , "g"(x) = (3+5x)/(4x−1)`

`("fog")(x) = "f(g"(x))`

= f`((3+5x)/(4x-1))`

=`((3+5x)/(4x-1)+3)/(4((3+5x)/(4x-1))-5`

= `(3+5x+12x - 3)/(12+20x-20x+5)`

= `(17x)/17`

= x

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 2: Functions - Miscellaneous Exercise 2 [पृष्ठ ३२]

APPEARS IN

संबंधित प्रश्‍न

Give examples of two functions fN → Z and gZ → Z such that g o f is injective but gis not injective.

(Hint: Consider f(x) = x and g(x) =|x|)


Classify the following function as injection, surjection or bijection :

f : Z → Z, defined by f(x) = x2 + x


Classify the following function as injection, surjection or bijection :

f : R → R, defined by f(x) = x3 + 1


Classify the following function as injection, surjection or bijection :

f : R → R, defined by f(x) = 1 + x2


If f : A → B is an injection, such that range of f = {a}, determine the number of elements in A.


Let f : N → N be defined by

`f(n) = { (n+ 1, if n  is  odd),( n-1 , if n  is  even):}`

Show that f is a bijection. 

                      [CBSE 2012, NCERT]


If f : A → B and g : B → C are one-one functions, show that gof is a one-one function.


Let A = R - {3} and B = R - {1}. Consider the function f : A → B defined by f(x) = `(x-2)/(x-3).`Show that f is one-one and onto and hence find f-1.

                    [CBSE 2012, 2014]


Write the total number of one-one functions from set A = {1, 2, 3, 4} to set B = {abc}.


Which one the following relations on A = {1, 2, 3} is a function?
f = {(1, 3), (2, 3), (3, 2)}, g = {(1, 2), (1, 3), (3, 1)}                                                                                                        [NCERT EXEMPLAR]


Let

f : R → R be given by

\[f\left( x \right) = \left[ x^2 \right] + \left[ x + 1 \right] - 3\]

where [x] denotes the greatest integer less than or equal to x. Then, f(x) is
 


(d) one-one and onto


The domain of the function f: R → R defined by f(x) = `sqrt(x^2 - 3x + 2)` is ______


Let A = [–1, 1]. Then, discuss whether the following functions defined on A are one-one, onto or bijective:

k(x) = x2 


Let A = {1, 2, 3, ...n} and B = {a, b}. Then the number of surjections from A into B is ______.


The number of bijective functions from set A to itself when A contains 106 elements is ____________.


The function f: R → R defined as f(x) = x3 is:


If log102 = 0.3010.log103 = 0.4771 then the number of ciphers after decimal before a significant figure comes in `(5/3)^-100` is ______.


Let f(x) = ax (a > 0) be written as f(x) = f1(x) + f2(x), where f1(x) is an even function and f2(x) is an odd function. Then f1(x + y) + f1(x – y) equals ______.


The trigonometric equation tan–1x = 3tan–1 a has solution for ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×