How to Divide the Region for a Double Integral over a Triangle?

[teng125]

double integral (6x^2 -40y)dA where it is a trianglewith vertices (0,3) , (1,1) and (5,3)

may i know how to divide the region according to this triangle??

 

[Integral]

The fisrt step is to draw a picture. It is then easier to see what needs to be done.

Please provide us with a complete problem statement. What you have posted is not clear.

 

[teng125]

∫∫ (for D) (6x^2-40y)dA
,D is the triangle with vertices (0,3), (1,1) and (5,3).

i have drawn the picture

 

[teng125]

but i don't know how to divide the region
pls help

 

[Gagle The Terrible]

I would divide it at the point (1,1) perpendicularly to the x-axis.
Then the two regions are bounded by a constant and a straight line .

 

[HallsofIvy]

I wouldn't divide it. I would integrate with respect to y. As y varies from 1 to 3, the left side is the the line from (0,3) to (1,1) and the right boundary is the line from (1,1) to (5,3). What are the equations of those two lines, written as x= ay+ b?

 

[Gagle The Terrible]

Even better !

 

[teng125]

[What are the equations of those two lines, written as x= ay+ b?]


do u mean we have to formulate another eqn ??or just integrate with respect to the axis coordinate using the eqn given??