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#26 2011-03-02 01:06:47
- Alive
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Re: Functions and Transformations.. one step at a time..
Okay so now.. the domain and range?
All things can be forgiven if we can progress.
Yusuf Islam (formerly known as Cat Stevens)
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#27 2011-03-02 01:18:16
- bobbym
- bumpkin
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Re: Functions and Transformations.. one step at a time..
Please look here:
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#28 2011-03-02 01:30:42
- Alive
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Re: Functions and Transformations.. one step at a time..
Using this to get the domain?
Last edited by Alive (2011-03-02 01:30:59)
All things can be forgiven if we can progress.
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#29 2011-03-02 01:35:34
- bobbym
- bumpkin
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Re: Functions and Transformations.. one step at a time..
I forget the problem which one are we working on?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#30 2011-03-02 01:38:13
- Alive
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Re: Functions and Transformations.. one step at a time..
We were working on (Truncus)
The actual question has 4 at the end as -4... I typed it wrong from my textbook.... which won't matter in this case? Cause there may be questions like these lying around?
Last edited by Alive (2011-03-02 01:41:40)
All things can be forgiven if we can progress.
Yusuf Islam (formerly known as Cat Stevens)
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#31 2011-03-02 01:51:10
- bobbym
- bumpkin
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Re: Functions and Transformations.. one step at a time..
The domain is whatever can go into the function that makes it work ( or is defined ). Everything works in x except for -3. When x is -3 we have 0 on the bottom. That is illegal. The domain is all x except -3
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#32 2011-03-02 01:56:35
- Bob
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Re: Functions and Transformations.. one step at a time..
hi Alive,
This time I think it is your question. 
I posted a diagram a while back on domain and range. It's at post #5 on
http://www.mathisfunforum.com/viewtopic.php?id=14957
Apparently that OP didn't need that so I'll re-cycle it to you.
Generally, in a problem the questioner states the domain at the start, because it can change the whole question otherwise.
If I had to make one up for
then I'd say x can be any real number but -3.
The range can be deduced from the function once you have a domain.
The second term is always positive (before you minus it) => you can never get a value for the function more than 4.
You cannot actually achieve 4 either as it's an asymptote but approaching x = 3 from either side sends y to minus infinity
so the range would appear to be 4 > f(x) > -∞
Bob
Last edited by Bob (2011-03-02 01:59:12)
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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#33 2011-03-02 02:03:57
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Re: Functions and Transformations.. one step at a time..
Thanks for the effort guys, it all makes sense to me now
All things can be forgiven if we can progress.
Yusuf Islam (formerly known as Cat Stevens)
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#34 2011-03-02 02:06:32
- Bob
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Re: Functions and Transformations.. one step at a time..
Excellent!
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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