Evaluate the Line Integral $\frac { 1 } { 2 } \int _ { C } x d y - y d x$

Short Answer

Evaluate the line integral $\frac { 1 } { 2 } \int _ { C } x d y - y d x$ where $C$ is the curve from $( 0,0 )$ to $( 1,0 )$ , to $( 1,2 )$ to $( 0,2 )$ , then to $( 0,0 )$ .