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April 29, 2026, 06:49:19 am

Author Topic: methods help  (Read 3894 times)  Share 

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hard

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methods help
« on: April 13, 2009, 03:28:12 pm »
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find the maximal dominan. Thing is, i don't think there's a q in the book that looks like this.

The range of the function with the equation i got (2,infinte) but the answer says otherwise.

the inverse of

TrueTears

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Re: methods help
« Reply #1 on: April 13, 2009, 03:32:21 pm »
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do you mean ?

if so just remember you can not divide by 0

so



so your domain is R\{}

if you meant

then its just a straight line, the maximal domain is R
« Last Edit: April 13, 2009, 03:39:14 pm by TrueTears »
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Re: methods help
« Reply #2 on: April 13, 2009, 03:36:35 pm »
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To find the range of

Sketch the graph, it is a hyperbola with domain x>0 so range is just
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hard

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Re: methods help
« Reply #3 on: April 13, 2009, 03:39:42 pm »
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do you mean ?

if so just remember you can not divide by 0

so



so your domain is R\{}

=/= means not equal to, I don't know how to do it on latex lols

if you meant

then its just a straight line, the maximal domain is R
the former is correct but thing is, in the multiple choice there is no answer with R\{}

EvangelionZeta

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Re: methods help
« Reply #4 on: April 13, 2009, 03:41:08 pm »
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The second one is a hyperbola, so sketch it first to see what it looks like.

Now, note that there are two halves.  There are asymptotes at x=0 and y=1, and since we're only interested in the upper half of the graph (the one that is on the right side of x=0), we only want everything that's within the curve which looks like an L.

Therefore the range is (1, infinite).



For the last one, make it into turning point form.

So

f(x)=(x-1)^2-1

Replace x with y.

x=(y-1)^2-1
x+1=(y-1)^2
(x+1)^[1/2]=y-1

Inverse f(x)=(x+1)^[1/2]+1
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EvangelionZeta

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Re: methods help
« Reply #5 on: April 13, 2009, 03:42:52 pm »
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do you mean ?

if so just remember you can not divide by 0

so



so your domain is R\{}

=/= means not equal to, I don't know how to do it on latex lols

if you meant

then its just a straight line, the maximal domain is R
the former is correct but thing is, in the multiple choice there is no answer with R\{}

Could you list the multiple choice answers that they give?
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hard

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Re: methods help
« Reply #6 on: April 13, 2009, 03:44:56 pm »
0
do you mean ?

if so just remember you can not divide by 0

so



so your domain is R\{}

=/= means not equal to, I don't know how to do it on latex lols

if you meant

then its just a straight line, the maximal domain is R
the former is correct but thing is, in the multiple choice there is no answer with R\{}

Could you list the multiple choice answers that they give?
[3, infinite)
(-infinite, 3]
(0,infinite)
(3, infinite)
(-infinite, 3)

EvangelionZeta

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Re: methods help
« Reply #7 on: April 13, 2009, 03:47:37 pm »
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The only thing which would make sense is if the (3-x) was all under the root sign (or ^[1/2]).   

In that case, 3-x must>0, since you can't divide by 0 or have a negative root.

Therefore, 3-x>0
3>x
x=(negative infinite, 3)
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TrueTears

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Re: methods help
« Reply #8 on: April 13, 2009, 04:07:32 pm »
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The only thing which would make sense is if the (3-x) was all under the root sign (or ^[1/2]).   

In that case, 3-x must>0, since you can't divide by 0 or have a negative root.

Therefore, 3-x>0
3>x
x=(negative infinite, 3)
yeah is the question meant to have square root ALL around the 3-x?
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hard

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Re: methods help
« Reply #9 on: April 13, 2009, 04:35:12 pm »
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The only thing which would make sense is if the (3-x) was all under the root sign (or ^[1/2]).   

In that case, 3-x must>0, since you can't divide by 0 or have a negative root.

Therefore, 3-x>0
3>x
x=(negative infinite, 3)
yeah is the question meant to have square root ALL around the 3-x?
yeee

TrueTears

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Re: methods help
« Reply #10 on: April 13, 2009, 04:37:26 pm »
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anything under a square root must be larger or equal to 0

so



so
« Last Edit: April 13, 2009, 06:40:11 pm by TrueTears »
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hard

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Re: methods help
« Reply #11 on: April 13, 2009, 04:38:50 pm »
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anything under a square root must be larger or equal to 0

so



so
ahhh yee thanks for that.

EvangelionZeta

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Re: methods help
« Reply #12 on: April 13, 2009, 06:16:11 pm »
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It's not (-infinite, 3], since the initial equation is 1/[(3-x)^(1/2)].  Root of 0 is 0, and 1/0 is undefined.

(-infinite, 3) is the answer...
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Re: methods help
« Reply #13 on: April 13, 2009, 06:49:09 pm »
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It's not (-infinite, 3], since the initial equation is 1/[(3-x)^(1/2)].  Root of 0 is 0, and 1/0 is undefined.

(-infinite, 3) is the answer...
sorry, my bad.
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Re: methods help
« Reply #14 on: April 13, 2009, 08:29:00 pm »
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Just shows even the best of us make mistakes.  =p
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