#Not sure how the problem solving logic works here
1 messages · Page 1 of 1 (latest)
- Wait patiently for a helper to come along.
- Once someone helps you, say thank you and close the thread with:
+close
- Feel free to nominate the person for helper of the week in #helper-nominations
- Do not ping the mods, unless someone is breaking the rules.
- If you're happy with the help you got here, and the server overall, you can contribute financially as well:
To check whether a piecewise function is continuous, you need to check for continuity on the boundary points of the pieces. So, here you need to ensure:
f(-1-) = f(-1+)
f(2-) = f(2+)
And combining (1) (2) and (3) you find the answer
so what your doing here is checking if there are limits that exist?
I previously understood this but I'm forgetting for some reason
Not just that they exist, but that they are equal.
Recall that a function f(x) is continuous at x = x0 if f(x0-) = f(x0) = f(x0+).
Here's a flowchart, just in case.
so what they're basically using is condition 2 (limit of f(x) exists) in order to solve for m and n, but what would theoretically happen if the limit did not exist?
also I'm starting to hate this question the more I look at it because of it's ambiguity
In that case the function would have a jump discontinuity for any values of m and n.
didn't indicate that the function was continuous, but instead asked to make it continuous
Not sure what you mean. The question is clear to me.
wait a minute is that why they set both limits equal to eachother?
That's because the function is continuous only for some values of m and n, not for all.
in order to make it continuous?
Yes.
but then why'd they throw in a -5 in there
In the statement?
Because the function is only defined for x ≥ -5.
not sure i understand
The domain of the function is x ≥ -5.
So, it only makes sense to talk about continuity on that set, not a larger one, as the function isn't defined outside of it.
hm okay, so it basically serves no purpose
Well, continuity is looked at on a certain set.
For example, if we have f(x) = 1/x, then it's continuous on its domain, but it clearly isn't continuous on the whole line.
okay let me try breaking down the logic of this question then:
- You need to make a non continuous function continuous
- To do so, you must set the limits of the end points equal to one another
- After you set the limits of the end points equal to one another you will find "m" and "n" by taking the limits for both sides
- Subtracting "m" and "n" to isolate for one variable will serve as a substitution and an answer to make the function g(x) continuous
You need to set the one sided limits at each point equal to each other. The limits at different points are independent.
You get a system and solve it for m and n.
only the first two steps are the thinky partsw
now you wouldn't do this unless you wanted to make the function continuous because setting two limits equal to one another is basically saying "yes this function is continuous at this value"
I think i get it now
hm okay wait
can a continuous function contain a hole?
because that's what I'm seeing in both of these points picked
Find the values of m and n for which this function is continuous:
f(x) = ...
...m(x - 1)^2 - n + 10, x < 0
...1, x = 0
...2m(x + 1)^3 - n, x > 0
No. It is, after all, continuous.