Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Applications of Derivatives

Question:

If it is given that at $x = 1$, the function $f(x) = x^4 - 62x^2 + 2ax +8$ attains its maximum value on the interval [0, 2], then the value of $a$ is:

Options:

120

60

0

-60

Correct Answer:

60

Explanation:

The correct answer is Option (2) → 60

Given: $f(x) = x^4 - 62x^2 + 2ax + 8$ attains maximum at $x=1$ on $[0,2]$

Derivative: $f'(x) = 4x^3 - 124x + 2a$

Maximum at $x=1 \Rightarrow f'(1) = 0$

$f'(1) = 4 - 124 + 2a = -120 + 2a = 0 \Rightarrow 2a = 120 \Rightarrow a = 60$

Answer: $a = 60$