मराठी

Let A = [-1, 1]. Then, Discuss Whether the Following Function From A To Itself is One-one, Onto Or Bijective : G(X) = |X| - Mathematics

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प्रश्न

Let A = [-1, 1]. Then, discuss whether the following function from A to itself is one-one, onto or bijective : g(x) = |x|  

बेरीज
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उत्तर

g(x) = |x|

Injection test:
Let x and y be any two elements in the domain (A), such that f(x) = f(y).

f(x) = f(y)

|x| = |y|

x = ± y

So, f is not one-one.

Surjection test :

For y = -1, there is no value of x in A.

So, f is not onto.

So, f is not bijective.

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पाठ 2: Functions - Exercise 2.1 [पृष्ठ ३२]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 2 Functions
Exercise 2.1 | Q 8.2 | पृष्ठ ३२

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