Mathematics

# Range of function $f ( x ) = \cos ( k \sin x )$ is [-1 , 1 ] then the least positive integral value of k will be

1

##### SOLUTION
$\cos(k \sin x)\in [-1,1]$
so $k \sin x=[-\pi,\pi]$
for $x\in R$   $\sin x \in [-1,1]$
$[-k,k]=[-\pi,\pi]$
so least integral
value is $1$

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Single Correct Medium Published on 17th 09, 2020
Questions 203525
Subjects 9
Chapters 126
Enrolled Students 86

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Q4 Subjective Medium
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