Differentiation Question 110
Question: $ \underset{x\to 0}{\mathop{\lim }}[ \frac{\sin (sgn(x))}{(sgn(x))} ], $ where [.] denotes the greatest integer function, is equal to
Options:
0
1
-1
D) Does not exist
Show Answer
Answer:
Correct Answer: A
Solution:
$ =\underset{x\to 0+}{\mathop{\lim }}[ \frac{\sin x}{x} ]=\underset{x\to 0+}{\mathop{\lim }}[ \frac{\sin x}{x} ]=1$
$ =\underset{x\to {0^{-}}}{\mathop{\lim }}[ \frac{\sin (x)}{ (x)} ]=\underset{x \to {0^{-}}}{\mathop{\lim }}[ \frac{\sin (x)}{x} ]$
$ =\underset{x\to {0^{-}}}{\mathop{\lim }}\sin(1) $ Hence, the given limit is 0.