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The Function F : R → R Defined by Is (A) One-one and onto (B) Many-one and onto (C) One-one and into (D) Many-one and into - Mathematics

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प्रश्न

The function f : R → R defined by

`f (x) = 2^x + 2^(|x|)` is 

 

विकल्प

  • one-one and onto

  • many-one and onto

  • one-one and into

  • many-one and into

MCQ
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उत्तर

(d) many-one and into

Graph for the given function is as follows.

A line parallel to X axis is cutting the graph at two different values.
Therefore, for two different values of x we are getting the same value of y.
That means it is many one function.[2 , ∞ )  and R is the co-domain of the given function.
Hence, Co-domain ≠ Range Therefore, the given function is into.

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अध्याय 2: Functions - Exercise 2.6 [पृष्ठ ७५]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 2 Functions
Exercise 2.6 | Q 4 | पृष्ठ ७५

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