मराठी

Let F Be an Invertible Real Function. Write ( F-1 of ) (1) + ( F-1 of ) (2) +..... +( F-1 of ) (100 )

Advertisements
Advertisements

प्रश्न

Let f be an invertible real function. Write ( f-1  of ) (1) + ( f-1  of ) (2) +..... +( f-1 of ) (100 )

Advertisements

उत्तर

Given that f  is an invertible real function. 

\[f^{- 1} o f = I, \text{where I is an identity function}.\]
\[So,\]
\[\left( f^{- 1} o f \right)\left( 1 \right) + \left( f^{- 1} o f \right)\left( 2 \right) + . . . + \left( f^{- 1} o f \right)\left( 100 \right)\]
\[ = I\left( 1 \right) + I\left( 2 \right) + . . . + I\left( 100 \right)\]
\[ = 1 + 2 + . . . + 100 \left( AsI\left( x \right) = x, \forall x \in R \right)\]
\[ = \frac{100\left( 100 + 1 \right)}{2}[\text{ Sum of first n natural numbers}=\frac{n\left( n + 1 \right)}{2}]\]
\[ = 5050\]

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 2: Functions - Exercise 2.5 [पृष्ठ ७४]

APPEARS IN

आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
पाठ 2 Functions
Exercise 2.5 | Q 26 | पृष्ठ ७४

व्हिडिओ ट्यूटोरियलVIEW ALL [5]

संबंधित प्रश्‍न

Check the injectivity and surjectivity of the following function:

f : Z → Z given by f(x) = x3


Show that the signum function f : R → R, given by

`f(x) = {(1", if"  x > 0), (0", if"  x  = 0), (-1", if"  x < 0):}`

is neither one-one nor onto.


Let S = {a, b, c} and T = {1, 2, 3}. Find F−1 of the following functions F from S to T, if it exists.

F = {(a, 3), (b, 2), (c, 1)} 


Let S = {a, b, c} and T = {1, 2, 3}. Find F−1 of the following functions F from S to T, if it exists.

F = {(a, 2), (b, 1), (c, 1)}


If the function `f(x) = sqrt(2x - 3)` is invertible then find its inverse. Hence prove that `(fof^(-1))(x) = x`


Give an example of a function which is one-one but not onto ?


Classify the following function as injection, surjection or bijection : f : N → N given by f(x) = x3


Classify the following function as injection, surjection or bijection :

f : R → R, defined by f(x) = |x|


Classify the following function as injection, surjection or bijection :

f : R → R, defined by f(x) = 3 − 4x


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


Find the number of all onto functions from the set A = {1, 2, 3, ..., n} to itself.


Suppose f1 and f2 are non-zero one-one functions from R to R. Is `f_1 / f^2` necessarily one - one? Justify your answer. Here,`f_1/f_2 : R → R   is   given   by   (f_1/f_2) (x) = (f_1(x))/(f_2 (x))  for all  x in R .`


Give examples of two functions f : N → N and g : N → N, such that gof is onto but f is not onto.


If f(x) = |x|, prove that fof = f.


if f (x) = `sqrt (x +3) and  g (x) = x ^2 + 1` be two real functions, then find fog and gof.


Let A = {1, 2, 3, 4}; B = {3, 5, 7, 9}; C = {7, 23, 47, 79} and f : A → B, g : B → C be defined as f(x) = 2x + 1 and g(x) = x2 − 2. Express (gof)−1 and f−1 og−1 as the sets of ordered pairs and verify that (gof)−1 = f−1 og−1.


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]


If f : R → (−1, 1) defined by `f (x) = (10^x- 10^-x)/(10^x + 10 ^-x)` is invertible, find f−1.


If f : A → A, g : A → A are two bijections, then prove that fog is a surjection ?


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


If f : R → R defined by f(x) = 3x − 4 is invertible, then write f−1 (x).


Let A = {x ∈ R : −4 ≤ x ≤ 4 and x ≠ 0} and f : A → R be defined by \[f\left( x \right) = \frac{\left| x \right|}{x}\]Write the range of f.


If f : R → R is defined by f(x) = 3x + 2, find f (f (x)).


If the mapping f : {1, 3, 4} → {1, 2, 5} and g : {1, 2, 5} → {1, 3}, given by f = {(1, 2), (3, 5), (4, 1)} and g = {(2, 3), (5, 1), (1, 3)}, then write fog. [NCERT EXEMPLAR]


If a function\[f : [2, \infty )\text{ to B defined by f}\left( x \right) = x^2 - 4x + 5\] is a bijection, then B =


Which of the following functions from

\[A = \left\{ x \in R : - 1 \leq x \leq 1 \right\}\]

 


Let  \[f\left( x \right) = \frac{1}{1 - x} . \text{Then}, \left\{ f o \left( fof \right) \right\} \left( x \right)\]

 


Let R be the set of real numbers and f: R → R be the function defined by f(x) = 4x + 5. Show that f is invertible and find f–1.


Let N be the set of natural numbers and the function f: N → N be defined by f(n) = 2n + 3 ∀ n ∈ N. Then f is ______.


Let f: R → R be defined by f(x) = 3x – 4. Then f–1(x) is given by ______.


Let X = {1, 2, 3}and Y = {4, 5}. Find whether the following subset of X ×Y are function from X to Y or not

g = {(1, 4), (2, 4), (3, 4)}


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

k(x) = x2 


Let f : R → R be defind by f(x) = `1/"x"  AA  "x" in "R".` Then f is ____________.


Prove that the function f is surjective, where f: N → N such that `f(n) = {{:((n + 1)/2",", if "n is odd"),(n/2",", if  "n is even"):}` Is the function injective? Justify your answer.


Let x is a real number such that are functions involved are well defined then the value of `lim_(t→0)[max{(sin^-1  x/3 + cos^-1  x/3)^2, min(x^2 + 4x + 7)}]((sin^-1t)/t)` where [.] is greatest integer function and all other brackets are usual brackets.


A perfect one-to-one matching between users and unique IDs is similar to:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×