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Which of the Following Functions from a to B Are One-one and onto F3 = {(A, X), (B, X), (C, Z), (D, Z)} ; a = {A, B, C, D,}, B = {X, Y, Z}.

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प्रश्न

 Which of the following functions from A to B are one-one and onto ?  

f3 = {(ax), (bx), (cz), (dz)} ; A = {abcd,}, B = {xyz}. 

योग
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उत्तर

f3 = {(ax), (bx), (cz), (dz)} ; A = {abcd,}, B = {xyz}

Injectivity:
f3 (a) = x
f3 (b) = x
f3 (c) = z
f3 (d) = z

⇒ a and b have the same image x. (Also c and d have the same image z)
So, f3 is not one-one.

Surjectivity:
Co-domain of f1 ={x, y, z} 
Range of f1 =set of images  =  {x, z}
So, the co-domain  is not same as the range.
So, f3 is not onto.

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अध्याय 2: Functions - Exercise 2.1 [पृष्ठ ३१]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 2 Functions
Exercise 2.1 | Q 2.3 | पृष्ठ ३१

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