JEE Main 2021 — Application Of Derivatives Question with Solution
From: JEE Main 2021 (Online) 26th February Evening Shift
Question
Let a be an integer such that all the real roots of the polynomial
2x5 + 5x4 + 10x3 + 10x2 + 10x + 10 lie in the interval (a, a + 1). Then, |a| is equal to ___________.
2x5 + 5x4 + 10x3 + 10x2 + 10x + 10 lie in the interval (a, a + 1). Then, |a| is equal to ___________.
Enter your answer
Show full solutionCorrect answer: 3
Correct answer
3
Step-by-step explanation
Let,
f(x) is strictly increasing function. Since, it is an odd degree polynomial it will have exactly one real root.
Now, by observation.
has at least one root in
|a| = - 2
f(x) is strictly increasing function. Since, it is an odd degree polynomial it will have exactly one real root.
Now, by observation.
has at least one root in
|a| = - 2
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