I'm really confused on how to do this: Find the indicated limit, if it exists. limit of f of x as x approaches 5 where f of x equals 5 minus x when x is less than 5, 8 when x equals 5, and x plus 3 when x is greater than 5
please write it out, or draw it.
I think I can get it formatted :) One sec.
\[\Large\rm f(x)=\cases{5-x,&x < 5\\ \rm 8\qquad~,&x = 5\\ \rm x+3,&x > 5}\]So this is our f(x), yes? Please don't look at my code, it's so sloppy lol
We don't actually care what the function equals AT x=5. The limit tells us what happens as we get closer and closer, but not actually at the location. So we'll ignore the middle piece.
When we approach from the left side, \[\Large\rm \lim_{x\to5^-}f(x)=\lim_{x\to5^-}(5-x)\] We use the branch of our piece-wise function that corresponds to where we are.
Evaluating the limit tells us that the function is approaching 0 from the left side. Understand what I did there? Do you think you can do the right sided limit?
0 and 8
@zepdrix
Is this the piece wise function?
so it would be dne bc 0 isn't equal to 8 right?
Yes, very good! :) The limit from the left does not agree with the limit from the right. So the limit of the function, as x approaches 5, does not exist.
thanks for the help :) and sorry i took long
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