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Let A = [-1, 1]. Then, Discuss Whether the Following Functions From A To Itself is One-one, Onto Or Bijective : H(X) = X2

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प्रश्न

Let A = [-1, 1]. Then, discuss whether the following functions from A to itself is one-one, onto or bijective : h(x) = x2 

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उत्तर

 h(x) = x2

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

f(x) = f(y)

x2 = y2

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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अध्याय 2: Functions - Exercise 2.1 [पृष्ठ ३२]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 2 Functions
Exercise 2.1 | Q 8.3 | पृष्ठ ३२

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