The set of value of k, for which the function $f(x)=kx^3+5$ is decreasing is :
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (-∞, 0)
$f(x)=kx^3+5$
for $f(x)$ to be decreasing, $f'(x)<0$
$⇒k2x^2<0$
$⇒k<0⇒(-∞, 0)$
The set of value of k, for which the function $f(x)=kx^3+5$ is decreasing is :
Correct answer: option 2
The correct answer is Option (2) → (-∞, 0)
$f(x)=kx^3+5$
for $f(x)$ to be decreasing, $f'(x)<0$
$⇒k2x^2<0$
$⇒k<0⇒(-∞, 0)$