G.MATH
VECTOR INTEGRAL CALCULUS
Line Integral example

In order for us to get acquainted with the line integral, let us look at a simple example.

VIDEO LECTURE


MAIN CONCEPTS
Find , substitute component functions, integrate w.r.t parameter.
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COMMENTS
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CONCEPT
Lets evaluate  where  and C is specified by  and .

We first need to check whether the position vector is smooth.  We have  which is continuous in the interval so C is smooth. Calculating the dot product gives us

At this point, the vector field is still defined as x, y, and z. We need to substitute the component functions of  as we are only concern with points on the curve C.

On C, ,  and . Substituting into  gives us

 

We can now integrate this function w.r.t t in the interval from 0 to 1.

 

We sum up by saying again to evaluate the line integral, we find the dot product , substitute the component functions in terms of t, and integrate w.r.t to t.

All information presentated, less questions and exercises, is original content of Donny, with slight references to various books.
Video courtesy of YouTube.com service.
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