ExamBro
ExamBro
JEE Advanced · Mathematics · 25. AOD

Paragraph:
Consider the polynomial \(f(x)=1+2 x+3 x^2+4 x^3\). Let \(s\) be the sum of all distinct real roots of \(f(x)\) and let \(t=|s|\).Question:
The function \(f^{\prime}(x)\) is

  1. A
    increasing in \(\left(-t,-\frac{1}{4}\right)\) and decreasing in \(\left(-\frac{1}{4}, t\right)\)
  2. B
    decreasing in \(\left(-t,-\frac{1}{4}\right)\) and increasing in \(\left(-\frac{1}{4}, t\right)\)
  3. C
    increasing in \((-t, t)\)
  4. D
    decreasing in \((-t, t)\)
Verified Solution

Answer & Solution

Correct Answer

(B)
decreasing in \(\left(-t,-\frac{1}{4}\right)\) and increasing in \(\left(-\frac{1}{4}, t\right)\)

Step-by-step Solution

Detailed explanation

Figure is self explanatory

From JEE Advanced
Explore more questions on app