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Author The Maths Thread!
k4m!k4ze
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Joined: Oct 02, 2004
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From: CBE
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Posted: 2004-10-29 12:31
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x = -1 and x = -1/2

Same technique as above

y=2x+1
y^2=2x^2+x

subst y value in eqn 1 in eqn 2

(2x+1)^2=2x^2+x
=> 2x^2+3x+1=0
=> 2x^2 + 2x + x + 1 = 0
=> (2x + 1) ( x +1 ) = 0

so u get x, subst both values in eqn 1 to get y values
If at first you don't succeed, destroy all evidence of your attempt !!
50Cent
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From: ...whatever psycho!!!
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Posted: 2004-10-29 12:42
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Quote:

On 2004-10-29 12:31:08, kllr_dude wrote:
x = -1 and x = -1/2

Same technique as above

y=2x+1
y^2=2x^2+x

subst y value in eqn 1 in eqn 2

(2x+1)^2=2x^2+x
=> 2x^2+3x+1=0
=> 2x^2 + 2x + x + 1 = 0
=> (2x + 1) ( x +1 ) = 0

so u get x, subst both values in eqn 1 to get y values




ah right so

y=(2 x -1) +1
y=-1

and
y=(2 x -1/2)+1
y=0

i think.

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fatreg
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Posted: 2004-10-30 15:44
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This so isnt the maths i did at school!

and i went to a grammar school? what went wrong!?

we were all about algebra, but saying that i never did get all the z,y's so maybe i aint got a hope in hell of getting calculus?

fatreg
kimcheeboi
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Joined: Dec 19, 2003
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From: Abducted by hot blondes to Les
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Posted: 2004-11-17 01:11
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help me with series, peeps!

power, taylor, and maclaurin series! [addsig]
maddav
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Joined: Dec 01, 2002
Posts: 356
From: Nottingham, UK
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Posted: 2004-11-18 20:57
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I need help, i just can't work out what to do, I know about half of this problem, and the answer, but I need to know how to finish it, I'm sure it's really simple but I just can't get my head round it, here it is:

I need the gradient for the curve f(x) at point A (2,13)

f(x) = 3x² + 2x¯¹
f¹(x) = 6x - 2x¯²

I'm sure for the gradient, i need to do something like substituting the x co-ordinate value, but then I don't know what to do next:
f¹(2) =

Help me please
kimcheeboi
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From: Abducted by hot blondes to Les
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Posted: 2004-11-19 01:32
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since f'(x) is he slope of the tangent line try finding the slope of the line using subistitution and use the equation of a line (y=mx+b) to find the tangent line at the point A

gradient = tangent line right? [addsig]
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