Prelim 2016 Maths Help Thread (3 Viewers)

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InteGrand

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Um...b/c there are answers for a reason...
I think you missed the point.

I know what the Q's mean, it's just they're technically not written right. If a function is only defined for x larger than 1, then it's meaningless to sub. in a value less than 1.

What the Q's meant was something like treat f-inverse as the inverse of the function f*, where f* is the function f restricted to x >= 1, where f is the function defined for all real x by *insert formula*.

(Unless you made a typo somewhere.)
 
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eyeseeyou

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I think you missed the point.

I know what the Q's mean, it's just they're technically not written right. If a function is only defined for x larger than 1, then it's meaningless to sub. in a value less than 1.

What the Q's meant was something like treat f-inverse as the inverse of the function f*, where f* is the function f restricted to x >= 1, where f is the function defined for all real x by *insert formula*.
Uh...You make my life hard Integrand
 

eyeseeyou

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More I need help with:

2.Given g(x)=(x+1)^2+3,x≤-1
a.g^(-1) (x)=(x+1)^2+3,x≤-1
b.g^(-1) (g(0))
c.g^(-1(g(b)) ),b>1

BTW Shuuya, if it's subbing then can you show me how you did it? (just need to check with the answers if you are doing it right or not)
Shuuya?
 

leehuan

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Um...could you please explain the subbing into the f^-1(x) part???

I don't get it
You're joking...

Go back to revising functions before doing inverse functions.

Established above: f-1(x) = 1+√(x-2)
BECAUSE we know f(3) = 6

f-1(f(3)) = f-1(6) = 1+√(6-2)

This is exactly what I mean by knowing your basics before you tackle the hard stuff.
 

eyeseeyou

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BTW I remember you all level SOS maths thread. I liked that thread until Trebla had to close it :(
 

leehuan

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BTW I remember you all level SOS maths thread. I liked that thread until Trebla had to close it :(
I just made like 20 threads afterwards. Still was fine. But I think next semester I'm making a MATH12xx and discrete math thread in the uni section.
 

Nailgun

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omg i love this thread

I can't wait until eyeseeyou starts doing 4U
 
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