Prelim 2016 Maths Help Thread (4 Viewers)

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eyeseeyou

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For 1 I used the differentation of the surd rule and got 1/ 2* squareroot of (x-3)

Could you retry the question by subbing it back in bc when I sub it back in it doesn't seem to work
 

InteGrand

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For 1 I used the differentation of the surd rule and got 1/ 2* squareroot of (x-3)

Could you retry the question by subbing it back in bc when I sub it back in it doesn't seem to work
 
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eyeseeyou

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How do you simplify this further g(x)=x^3

I got yp to 1/3x^-2/3
 

eyeseeyou

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BTW if anyone here has nothing to do please post in the "count to 100 before a moderator posts" thread
 

leehuan

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Basically all you had to do was find the inverse and sub in x into the equation
You actually don't unless the question specifically asks for g-1(x), marking g-1(y) as wrong.
 

eyeseeyou

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1. f(x)=(x-1)^2+3, x>=1

Find f^-1'(x),x>3

2. g^-1'=x^3

Find g^-1'(x)

3. h(x)=x^3-3x, -1<x<1 find h^-1'(0)
I am getting stuck with this

What I did was y=x^3-3x, -1<x<3
then x=y^3-3y, -1<y<3

Then what do I do Integrand?
 

InteGrand

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I am getting stuck with this

What I did was y=x^3-3x, -1<x<3
then x=y^3-3y, -1<y<3

Then what do I do Integrand?
Like I said before, it is impractical to try inverting that function.

The answer is just 1/h'(0), because h(0) = 0 (a = 0 and b = 0 in the Inverse Function Theorem formula). Since h'(0) = -3, the answer is -1/3.
 

eyeseeyou

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Like I said before, it is impractical to try inverting that function.

The answer is just 1/h'(0), because h(0) = 0 (a = 0 and b = 0 in the Inverse Function Theorem formula). Since h'(0) = -3, the answer is -1/3.
what?
 

eyeseeyou

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Consider the function f(x)=(x^3+8x)/8
a. Show that f(x) is an increasing function
b. Find the equation of the tangent to y=f(x) at the origin
c. Using equal scales of axes, sketch a graph of y=f(x) over the domain -2=<x=<2 and draw its tangent at the origin
d. explain why an inverse exists and draw a grapg of y=f^-1(x) on your diagram
e. Solve f^-1(x)=8
f. Evaluate Integral of 3 to 0 f^-1(x) dx
 

eyeseeyou

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BTW Integrand just realised but you've been here all night lol
 

Trebla

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eyeseeyou you still haven't answered my questions
 
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