Inverse Trigonometric Functions Question 86
Question: The complete solution set of $ {{[co{t^{-1}}x]}^{2}}-6[co{t^{-1}}x]+9\le 0, $ Where [.] denotes the greatest integer function, is
Options:
A) $ (-\infty ,\cot 3] $
B) $ [\cot 3,\cot 2) $
C) $ [\cot 3,\infty ) $
D) None of these
Show Answer
Answer:
Correct Answer: A
$ {{[co{t^{-1}}x]}^{2}}-6[co{t^{-1}}x]+9\le 0 $
$ \Rightarrow {{([co{t^{-1}}x]-3)}^{2}}\le 0\Rightarrow [co{t^{-1}}x]=3 $
$ \Rightarrow 3\le {{\cot }^{-1}}x<4\Rightarrow x\in (-\infty ,\cot 3] $
BETA
