help pls (ocr additional maths paper)

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hughy
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#1
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#1
I drew up a little diagram in photoshop of the question I'm stuck on..

http://jdesign.org/question.jpg

I think I've done it right so far, but I've written the question down just in case.

I need to know how to find the area (idk if this is even the right place to ask but I am desperate )
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Mat666
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#2
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Find where curve algebra = 0

x^2 - 3x = 0
x(x - 3) = 0
so x = 0 or 3


You've drawn the area wrong... the curve passes through (0,0) surely?

If so:

Area of Triangle - Integral between 0 and 1 of (x^2 - 3x)
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thenarbisbanned
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put the 2 lines equal to each other and rearrange...integrate that equation for the area of the sail..
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hughy
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#4
(Original post by Mat666)
Find where curve algebra = 0

x^2 - 3x = 0
x(x - 3) = 0
so x = 0 or 3


You've drawn the area wrong... the curve passes through (0,0) surely?

If so:

Area of Triangle - Integral between 0 and 1 of (x^2 - 3x)

Yeah, the curve passes through (0, 0) I drew it wrong lol.

I'm really new to all this stuff, so I don't really know what you're talking about Some school wants me to take a test to get in, and this was a q on last years paper :/
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Fermat
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(i) y = 3x - x²
y' = 3 - 2x
=======

(ii)B(1,2)
at x = 1, y' = 3 - 2 = 1
y' = 1
====
Tangent to y at B has gradient m = 1

y - y1 = m(x - x1)
y - 2 = 1.(x - 1)
y - 2 = x - 1
y = x + 1
======

(iii)
The tangent cuts the x-axis at y = 0
=>x = -1
=====
Therefore A is (0, -1)
===============

(iv)
Area of sail is area of triangle with AB as its hypotenuse minus the area under the curve y = 3x - x² from x = 0 to x = 1.
Area of triangle = A1 = ½.2.2 = 2
A1 = 2 sq units
==========

A2 = ∫ {0 -> 1} 3x - x² dx
A2 = [3x²/2 - x³/3]{0 -> 1}
A2 = 3/2 - 1/3
A2 = 7/6
======

A = A1 - A2
A = 2 - 7/6
A = 5/6
=====
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EconLou
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(Original post by hughy)
I drew up a little diagram in photoshop of the question I'm stuck on..

http://jdesign.org/question.jpg

I think I've done it right so far, but I've written the question down just in case.

I need to know how to find the area (idk if this is even the right place to ask but I am desperate )
Are you doing the additional maths FSMQ paper, I'm doing it at the moment aswell, I didn't think I would meet anyone who knew what it was!
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EconLou
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(Original post by hughy)
Yeah, the curve passes through (0, 0) I drew it wrong lol.

I'm really new to all this stuff, so I don't really know what you're talking about Some school wants me to take a test to get in, and this was a q on last years paper :/
have you worked through the textbook for add.maths, is it being taught to you at school, because this stuff you really need to be taught how to do.
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hughy
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(Original post by Louise_1988)
have you worked through the textbook for add.maths, is it being taught to you at school, because this stuff you really need to be taught how to do.
Heh, I just moved to the UK from Canada, and I don't really know much of anything in the additional mathematics paper. I'm just sort of going through last years paper and trying to teach myself whatever is covered in it.
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hughy
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Fermat thx for the help. You explained it well

Also thanks to everyone else
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