English

Let f: N → R be the function defined by f(x) = 2x-12 and g: Q → R be another function defined by g(x) = x + 2. Then (g o f) 32 is ______.

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Question

Let f: N → R be the function defined by f(x) = `(2x - 1)/2` and g: Q → R be another function defined by g(x) = x + 2. Then (g o f) `3/2` is ______.

Options

  • 1

  • 1

  • `7/2`

  • None of these

MCQ
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Solution

Let f: N → R be the function defined by f(x) = `(2x - 1)/2` and g: Q → R be another function defined by g(x) = x + 2. Then (g o f) `3/2` is none of these.

Explanation:

We have f(x) = `(2x - 1)/2` and g(x) = x + 2

gof`(3/2)` = g`(f(3/2))`

= `"g"((2 xx 3/2 - 1)/2)`

= g(1) = 1 + 2

= 3

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Chapter 1: Relations And Functions - Exercise [Page 16]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 45 | Page 16

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