Line integral uncertain about direction.

aleee
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Homework Statement


Evaluate \int[(3x-y)dx-xdy] where C consist of the parabola y=x^2 from (0,0) to (1,1) and then the line segment from (1,1) to (0,1)

Homework Equations


The Attempt at a Solution


i did the integral of the y=x^2
parametrized
x=t
y=t^2
from 0 to 1
then i got my 1/2
but for the line segment do i just take the the integral using
x=t
y=1
but for the interval do i use 0 to 1 or 1 to 0
 
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You want to go from (1,1) to (0,1) along (t,1). That makes it t=1 to t=0, right?
 
so would i get \int_1^0\\(3t-1)dt
and would i just integrate it like that
i wouldn't require a negative because its a parametric correct?
 
aleee said:
so would i get \int_1^0\\(3t-1)dt
and would i just integrate it like that
i wouldn't require a negative because its a parametric correct?

Sure. You don't have to add any extra signs. Just work out what it is and add it to your first path.
 
thanks for the help!
 
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