JEE Main 2019 — Mathematical Reasoning Question with Solution
JEE Main 2019 (11 Jan Shift 1)
Question
If is false and is true, then which one of the following statements is a tautology?
Choose an option
Show full solutionCorrect option: B
Correct answer
B
Step-by-step explanation
is false and is true As is false
False is true
Hence is false
Option (1): says ,
Since is false
Hence can either be true or false
Option (2): says
is false
Since, is true and
is also true
Hence, it is a tautology
Option (3):
i.e.
It can either be true or false
Option (4):
Since, is false
Hence, is false.
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This is a previous-year question from JEE Main 2019, covering the Mathematical Reasoning chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.