Q17 of 99 Page 34

Show that the function


is many - one into.


Find (i) (ii) (iii)


(iv)


(i)


Here, x = 1/2,which is rational


∴f(1/2) = 1


(ii)


Here, x = √2,which is irrational


∴f(√2) = - 1


(iii)


Here, x = ∏, which is irrational


= - 1


(iv)


Here,x = 2 + √3, which is irrational


∴f(2 + √3) = - 1


Ans. (i) 1 (ii) - 1 (iii) - 1 (iv) - 1


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15

Which of the following relations are functions? Give reasons. In case of a function, find its domain and range.

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Find the domain and range of the real function, defined by Show that f is many - one.

 1

Let A = {1, 2, 3, 4}. Let f : A → A and g : A → A,

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Let f : {3, 9, 12} → {1, 3, 4} and g : {1, 3, 4, 5} → {3, 9} be

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