I am trying to evaluate a line integral over the boundary of the area in the x-y plane between the parabola and the line , in an counterclockwise direction.
The integral is
Int((y^2-x)dx+(3x+y)dy) (still learning latex ...sorry)
Can someone please tell me: Do I have to split up the enclosed boundary into the straight line part and the parabola part, and do them separately? This is what I have done.
I have parametrised the line as
and the parabola separately as .
I then evaluated the line integrals separately and got -2 and 4.4
Not sure if I need to now simply add them as they are or add absolute values (I'm thinking the first one)
Could someone kind out there please check my first value of -2. The problem I encountered is : If dy/dt=0 then dy=0dt and does that mean the second part of the integral (ie the bit with 3x+y) just becomes 0?
Any help appreciated. Thanks.