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ntegrating w/ abs value?? (1 Viewer)

jkwii

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I = S (2- |x|) dx from 3 to -3.. do u use the graph?? like area??
 

Js^-1

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hmmm...No clue. Its not odd, so its not automatically zero. Maybe you have to integrate the parts seperately and add them? Like for x>0 and x<0? Integrating y=2-x from 0 to 3 and y=x-2 from -3 to 0. I have no idea if thats right or not, but thats how i'd try to do it.
 

conics2008

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use the fact that |x| = y=x and y = -x above the x axis
 

Templar

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Break the integral into 2 and |x|, and use the fact |x| is even
 

conics2008

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Here I will list the steps for you

i) draw 2-|x|
ii) You will notice that its made up of two equations y=2-x and y=2+x
iii) you can do this by integration or by normal area rules because these shapes are triangles
iiii) use the normal triangles. I will post graph
 
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jkwii

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ok cool but integration with limits is not the same as finding areas. go figure.

J.
 

conics2008

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jkwii said:
ok cool but integration with limits is not the same as finding areas. go figure.

J.
Integration is the process of find the area between a curve.
 

Trebla

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Using the definition:
| x | = x, if x ≥ 0
= - x, if x < 0

3-3(2 - |x|)dx = ∫30(2 - x)dx + ∫0-3(2 + x)dx

then integrate and evaluate...
 

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