Question

find the limit(if it exists), if not explain why.


lim
x--> 4- (3[[x]]-5)

Answer 1

can't make out your limit expression

Answer 2

limit as x-->4- (from the left) of

(3[[x]]-5)

[[absolute value.]]

Answer 3

In any limit, one of the first things you should do is simply substitute.
If you get a real answer, that is your answer, you are done!

so
Lime 3|x| - 5 as x ---> 4 -
= 3(4)-5 = 7

Try a value near 4 from the left
e.g. x = 3.9999
then 3|3.9999|-5 = 6.9997 , yup, close enough for 7