#integration by parts

40 messages · Page 1 of 1 (latest)

shrewd bane
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split the area into two

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so you have a triangle and like a curved bit

potent dome
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yes i already know that??

shrewd bane
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so what bit do you not know

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how to integrate it?

potent dome
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no i mean to like find the co ords

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i know the basics of splitting it but finding the co ords is so off putting

shrewd bane
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the only co- ords you need is when the line meets the x axis so when y of the line you calculated = 0

potent dome
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like how do u find this

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yes i know that omg

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we don't have the equation for line l

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y - e = (1/1+ln x) (x-e)

shrewd bane
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yh then y=0

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gives you the right pink co -ord

potent dome
shrewd bane
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it's the negative reciprocal

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so -1/1+lnx

potent dome
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omg yes i already know that im not fucking dumb

shrewd bane
potent dome
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the point is that's not the gradient

shrewd bane
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then you differentiated wrong

potent dome
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the gradient is -1/2 so how are u meant to go from -1/1+lnx to -0.5

potent dome
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are u fucking dumb

potent dome
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don't even try to help me if u don't know what ur doing bye

shrewd bane
thorny thorn
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Dont have to be so rude

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Sub in ur x coordinate into the gradient first then find the negative reciprocal

thorny thorn
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you know the normal is perpendicular to the tangent hence the gradient of the normal is the negative reciprocal of the tangent

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hence -1/2

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@potent dome

potent dome
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thanks though

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at least someone knows what they're doing

thorny thorn
potent dome
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yh

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substitute e into it