# Thread: computing flux through a surface

1. ## computing flux through a surface

Compute the flux of the vector field, $\vec{F}$, through the surface, S. $\vec{F} = 7x\vec{i} + y\vec{j} + z\vec{k}$ and S is the part of the surface z + 4x + 2y = 12 in the first octant oriented upward.

Can someone please guide me how to solve for this?

2. You have the method down as evidenced by your last post???

The only pblm might be the region of integration but let z = 0 and you have a triangle in the x-y plane.

N = 4i+2j+k F*N is no problem

The last pblm was more dificult

3. yes, I am actually confused by the limits of integration...

4. you have a triangle with vertices (0,0),(3,0) and (0,6)

the line segment from (0,6) to (3,0) has eqn y = -2x +6

So int y from 0 to -2x+6 and then x from 0 to 3

5. thanks for the guide