1. Which of the following sets are empty?
Justiſy,
a. (x:x N and 3 <x<4)
b. (x:x is a prime number lying between
17 and 19)
c. (x:x is prime and 19 SXS 23)
d. (x:x° + 2 = 0 and x e N)
e. (x:x e W and 13 sxs 14)
f. (Vowels in the word WISE)
Answers
Answer:
Parts (a) , (b) , (c) , (d) and (e) are empty
Step-by-step explanation:
Since
In Part (a)
x is natural number between 3 and 4 and we know no natural number exist between 3 and 4
So
Part (a) is empty.
Now
In Part (b)
x is prime number between 3 and 4 and we know no prime number exist between 17 and 19
So
Part (b) is empty.
Now
In Part (c)
x is prime number between 19 and 23 and we know no prime number exist between 19 and 23
So
Part (c) is empty.
Now
In Part (d)
x is natural number which satisfy the equation
x^0 + 2 = 0
⇒ 1 + 2 = 0 ∵ x^0 = 1 , ∀ x ∈ N
but 1 + 2 ≠ 0
So
No any natural number exist which satisfy the condition
Thus
Part (d) is empty.
Now
In Part (e)
x is whole number between 13 and 14 and we know no whole number exist between 13 and 14
So
Part (e) is empty.
Now
In Part (f)
we have to find the vowels in word WISE which are I and E
So
Part (f) is not empty.