# Thread: Line Integral and Green's Theorem

1. ## Line Integral and Green's Theorem

Hi,

In this and the following problem you will consider the integral

on the closed curve C consisting of the line segments from (0,0) to (3,4) to (0,4) to (0,0). Here, you evaluate the line integral along each of these segments separately

Evaluate the integral above by finding the integral from (0,0) to (3,4), adding the integral from (3,4) to (0,4), and adding the integral from (0,4) to (0,0):
= [______] + [________] + [______] = 63.9622574120271

The answer for this problem is 63.9622574120271 and I know it because I used the green's theorem to do it. In this case they want me to do it directly and I should end up with the same value if I add the answers up.

2. You want to parameterize each of the segments. For instance, the first segment is the line $\displaystyle y=\frac{4}{3}x$. Thus, $\displaystyle x=t, y=\frac{4}{3}t, dx=dt, dy=\frac{4}{3}dt$
Substitute and integrate for $\displaystyle t=0..3$.