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# Splitting a function into 2 intervals watch

1. Consider the function for

How should I split this into two intervals and ?

Thanks.
2. (Original post by AishaGirl)
Consider the function for

How should I split this into two intervals and ?

Thanks.
Just say that since the split interval does not account for it.
3. (Original post by RDKGames)
Just say that since the split interval does not account for it.
Can you explain a little more? Like how do I break it down to get the two intervals?
4. (Original post by AishaGirl)
Can you explain a little more? Like how do I break it down to get the two intervals?
Well the function is defined on so when it comes to the interval it disregards so your function get split such that is undefined.

In essence you have where

At least that's how I'd define across these two intervals anyway.
5. (Original post by RDKGames)
Well the function is defined on so when it comes to the interval it disregards so your function get split such that is undefined.

In essence you have where

At least that's how I'd define across these two intervals anyway.
so ?

Is this correct?
6. (Original post by AishaGirl)
so ?

Is this correct?
I'm not sure what you are trying to do here? Yes and the stationary point is indeed at but if that's following from the previous part then we have a problem.
7. (Original post by RDKGames)
I'm not sure what you are trying to do here? Yes and the stationary point is indeed at but if that's following from the previous part then we have a problem.
Yes this is a tad confusing.

Cosh is defined for all real but it's not clear what the OP is supposed to be doing here.
8. (Original post by RDKGames)
I'm not sure what you are trying to do here? Yes and the stationary point is indeed at but if that's following from the previous part then we have a problem.
I'm trying to find the interval on which is increasing. Now that I've split it into two intervals I can show that is always concave up? I think...
9. (Original post by AishaGirl)
I'm trying to find the interval on which is increasing. Now that I've split it into two intervals I can show that is always concave up? I think...
Well if you're trying to find when it is increasing, setting won't help with that as this is the stationary point when the function is neither increasing nor decreasing.

If a function is increasing on an interval then on that interval.

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