The value of b for which the function $f(x) = sin x - bx + C, $ where b and c are constants is decreasing for $x \in R$ is given by
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → $b> 1$
$f(x) = \sin x - bx + C$
$f'(x)=\cos x-b$
$max(\cos x)=1$
so for $f'(x)$ to be decreasing $b>1⇒f'(x)<0$ always