JEE Main 2021 — Functions Question with Solution
From: JEE Main 2021 (Online) 20th July Morning Shift
Question
Let [ x ] denote the greatest integer x, where x R. If the domain of the real valued function is ( , a) [b, c) [4, ), a < b < c, then the value of a + b + c is :
Choose an option
Show full solutionCorrect option: C
Correct answer
C2
Step-by-step explanation
For domain,
0
Case I :
When 0
and > 0
x ( , 3) [4, ) ...... (1)
Case II :
When 0
and < 0
x [2, 3) ..... (2)
So, from (1) and (2) we get
Domain of function
= ( , 3) [2, 3) [4, )
(a + b + c) = 3 + (2) + 3 = 2 (a < b < c)
Option (3) is correct.
0
Case I :
When 0
and > 0
x ( , 3) [4, ) ...... (1)
Case II :
When 0
and < 0
x [2, 3) ..... (2)
So, from (1) and (2) we get
Domain of function
= ( , 3) [2, 3) [4, )
(a + b + c) = 3 + (2) + 3 = 2 (a < b < c)
Option (3) is correct.
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