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Inverse trig question (1 Viewer)

Aysce

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This question comes from Question 7.b.v. 1996 HSC

v. Let a be a real number not in the domain found in part ii. Find f^-1(f(a))

The domain found was x >= 1. x=1 is also the axis of symmetry.

f(x) = 1/4 [(x-1)^2 + 7]
f^-1(x) = 1 + (4x-7)^1/2

Hopefully this information will suffice, explanations will be appreciated.
 
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?? It's just subbing into the formulas you found.

It's like if f(x) = x^2 & g(x) = 3x+5

g(f(x)) = 3[x^2] +5 = 3x^2 +5
 
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f^-1 [f(a)] = 1 + (4 [(1/4)[(a-1)^2+7] ] -7 )^(1/2)

= 1 + [ (a-1)^2 +7-7]^(1/2)

= 1+ (a-1)

=a
 

Aysce

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?? It's just subbing into the formulas you found.

It's like if f(x) = x^2 & g(x) = 3x+5

g(f(x)) = 3[x^2] +5 = 3x^2 +5
Yeah but you also have to sub in a certain value for a which should let you arrive at 2-a.
 

Carrotsticks

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Sorry if this is too small, here is another link where you can save it and hopefully see a larger size:

Untitled.jpg

Also, I think I said "B is on the left". I meant "B is on the right".
 
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Aysce

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Thank you very much for both of your help.

I am starting to worry for inverse questions. I can't quickly if at all, knock out the harder questions. :/
 

SpiralFlex

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Thank you very much for both of your help.

I am starting to worry for inverse questions. I can't quickly if at all, knock out the harder questions. :/
This is about the hardest it can get haha. (I doubt they are you anything more) I can find harder types for you if you want. (If you are paranoid)
 

Carrotsticks

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This is about the hardest it can get haha. (I doubt they are you anything more) I can find harder types for you if you want. (If you are paranoid)
Oh... it gets a lot harder... (or at least I've written a lot harder. Doubt they would go into that much detail in HSC though).
 

Aysce

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This is about the hardest it can get haha. (I doubt they are you anything more) I can find harder types for you if you want. (If you are paranoid)
Please, if you don't mind. I'm starting to lose grasp since I've lost confidence and my test is in 2 weeks. I want to perfect inverse trig.

(Yes confidence plays a MAJOR part in my performance)
 

SpiralFlex

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Please, if you don't mind. I'm starting to lose grasp since I've lost confidence and my test is in 2 weeks. I want to perfect inverse trig.

(Yes confidence plays a MAJOR part in my performance)
I'll see what I can find haha. Really just do all those "things" I gave you before and you'll be set. Most likely nothing above this will be tested in HSC as Carrot has said.
 

Aysce

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I'll see what I can find haha. Really just do all those "things" I gave you before and you'll be set. Most likely nothing above this will be tested in HSC as Carrot has said.
Yeah i will go through them, it's just the one's I've seen so far are pretty straightforward. It shows I can rote learn but I don't really understand inverse trig too welll...
 

Sy123

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Oh, if it isnt to stupid to ask, but may I have those questions as well please?

I have the task for this and applications of calc. in about 4 weeks and our examiner gives us crazy questions, and it wouldnt hurt for me to try some of these questions that you may have.

Thank You very much.
 

SpiralFlex

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Oh, if it isnt to stupid to ask, but may I have those questions as well please?

I have the task for this and applications of calc. in about 4 weeks and our examiner gives us crazy questions, and it wouldnt hurt for me to try some of these questions that you may have.

Thank You very much.
Sure thing, however they are just past papers I gave Aysce, I am sure you have them already. No such thing as a stupid question, life is about questions.
 

Sy123

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Oh ok, so the papers you gave to Aysce were past HSC papers?
If they were a school's one, or an independent or something, those are like gold to me heh.
 

SpiralFlex

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Oh ok, so the papers you gave to Aysce were past HSC papers?
If they were a school's one, or an independent or something, those are like gold to me heh.
Just name me the school's paper you want. We'll talk about this via PM later to avoid warnings. Also you have to wait a while haha, I have a lost list of people to go through.
 

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