If x=1 is a critical point of the function f(x)=(3x²+ax-2-a)eˣ, then

Option 1 - <p>x=1 is a local minima and x=-2/3</p>
Option 2 - <p>x=1 and x=-2/3 are local minima of f.<br><!-- [if !supportLineBreakNewLine]--><br><!--[endif]--></p>
Option 3 - <p>x=1 is a local maxima and x=-2/3 is a local minima of f.<br><!-- [if !supportLineBreakNewLine]--><br><!--[endif]--></p>
Option 4 - <p>x=1 and x=-2/3 are local maxima of f.</p>
13 Views|Posted 5 months ago
Asked by Shiksha User
1 Answer
V
5 months ago
Correct Option - 4
Detailed Solution:

f(x) = (3x²+ax-2-a)e?
f'(x) = (3x²+ax-2-a)e? + e?(6x+a)
= e?(3x²+(a+6)x-2)
∴ x=1 is a critical point
∴ f'(1)=0
∴ 3+a+6-2=0
a = -7
∴ f'(x) = e?(3x²-x-2)
= e?(3x+2)(x-1)


∴ maxima at x = -2/3
∴ minima at x = 1

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Maths Applications of Derivatives 2025

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