#Past Paper AS Question

53 messages · Page 1 of 1 (latest)

calm oar
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yuck

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ok so what do you know about integration

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@delicate thistle

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ok so

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yep

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yes you do

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exactly that

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and youve now solved it in about 2 mins

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nah its fine lmao im glad you worked it out

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yeah exactly

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all your brain needed apparently

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yuck

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ok so

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what have you tried so far

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yep

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ok so

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you got like 6x^2 - 34x + 40 right

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for your dy/dx whatever

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ok so

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now it says its a turning point at k

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what happens at turning points with gradients

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so at a stationary point the curve is

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like perfectly flat

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so the gradient is actually 0

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perfect yes

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solving that looks fun

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so solving that will tell you any points where the curve is flat so all your stationary points

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so these two points

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yeah i mean turning points

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exactly yes

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because at k its a turning point

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so youll be able to figure out what k is

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well itll be the one

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further along the x axis

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yep exactly

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wait no k is just that value

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so if you solve your 6x^2 - 34x + 40x = 0

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whatever it was

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youll get two x values

calm oar
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so you actually dont care about y for this question

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you only really care about k because

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thats the upper limit for your integration

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lets maybe actually do some of the working, might help us visualise when we have the numebrs

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the bigger x value yeah

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for k yeah

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oh yeah

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you integrate between

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0 and the bigger x value

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well you wanna show its equal to 256/3

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so hope to the lord that it ends up as 256/3

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coolio