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Find F −1 If It Exists : F : A → B, Where A = {0, −1, −3, 2}; B = {−9, −3, 0, 6} And F(X) = 3 X.

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प्रश्न

Find f −1 if it exists : f : A → B, where A = {0, −1, −3, 2}; B = {−9, −3, 0, 6} and f(x) = 3 x.

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उत्तर

A = {0, −1, −3, 2}; B = {−9, −3, 0, 6} and f(x) = 3 x.
Given: f(x) = 3 x
So,  f = {(0, 0), (-1, -3), (-3, -9), (2, 6)}
Clearly, this is one-one.
Range of f = Range of f =B
So, f is a bijection and, thus, f -1 exists.  
Hence,f -1= {(0, 0), (-3, -1), (-9, -3), (6, 2)}

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अध्याय 2: Functions - Exercise 2.4 [पृष्ठ ६८]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 2 Functions
Exercise 2.4 | Q 2.1 | पृष्ठ ६८

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