Question:

Let \(f:\mathbb{R}\to\mathbb{R}\) be a function such that \(f(x)=x^3+x^2f'(1)+xf''(2)+f'''(3)\), \(x\in\mathbb{R}\). Then \(f(2)\) equals -

Show Hint

\(f'(1),f''(2),f'''(3)\) are constants; differentiate the given relation to find them.
Updated On: Nov 5, 2026
  • 30
  • \(-2\)
  • \(-4\)
  • 8
Show Solution
collegedunia
Verified By Collegedunia

The Correct Option is B

Solution and Explanation

Let \(a=f'(1),\ b=f''(2),\ c=f'''(3)\). \(f'(x)=3x^2+2ax+b\), \(f''(x)=6x+2a\), \(f'''(x)=6\).
\(c=6\). \(b=f''(2)=12+2a\). \(a=f'(1)=3+2a+b\Rightarrow a=-3-b\).
Then \(b=12+2(-3-b)=6-2b\Rightarrow b=2,\ a=-5\).
\(f(x)=x^3-5x^2+2x+6\), so \(f(2)=8-20+4+6=-2\).
Answer: (2) \(-2\)
Was this answer helpful?
0
0