#how do i even do this

87 messages · Page 1 of 1 (latest)

hardy flax
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so this is straight away integration

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because it wants the area of a curve

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and we've been given an equation

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so it must be integration

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now for integration, we need to find the limits

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these are essentially the roots to the equation

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so find the roots

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(in this q, a is a constant)

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find the roots of the equation y=a²-x²

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what do you think

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use a bit of common sense

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we're finding the roots

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how would you find the roots of y=x²-5x+6

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I mean like

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yeah but

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what do you have to do

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there's a y

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how can you find the roots with a y in the equation

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set y=0

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this is gcse knowledge

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about solving quadratics

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anyways

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?

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yeah it is y=0

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I was just trying to get you to work it out

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anyways

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so, find the roots of y=a²-x²

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keep going

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solve for x

rotund stratus
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what do you call it when u

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take away

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two square numbers

hardy flax
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yep

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there are two solutions

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yep

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so now the integral between a and -a of a²-x² = 36

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have you been taught what integration is

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the integral is the big s shaped thing

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yep so find the integral between a and -a of that equation

rotund stratus
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it gives you the area beneath the curve

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if you substitute in limits

hardy flax
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read the question

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it's not the y

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I'm saying the integral between those two limits is = 36

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no

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y is not 36

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the integral

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is = to 36

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very very different

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????

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integrate!!!

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just integrate it

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🤗

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for the 4th time

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it is NOT equal to 36

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the integral is = 36

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very different

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yes

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integrate that

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a is a constant

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not a variable

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we are integrating with respect to x

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constants are terms that do not change, like the number 7
variables can change depending on what we want to make them
x is a variable because I could make x whatever I want

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a is a constant however because it has a set value

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because a² does not integrate to 1/3a³

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whenever you are integrating a constant term, you add an x

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so integral of a² -> a²x

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it's not equal to y

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it's just the integral

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the y disappears

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good

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now because we're doing definite integration

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the + c doesn't matter

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no it's not unless you did your limits with the + c

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then yes it is an issue

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yes

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carry on

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yes

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no

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limits are the things that go on the top and bottom of an integral

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they tell us between what values we are integrating

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so we can find the area of the curve between those two values

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ydp

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yep

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yes

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well done