Region in the XY plane over which the double integral is taken.

30 Views Asked by At

$$\int_{-1}^1\int_{1+x}^1\cos(x+y)e^{(y-x)}\,dy\,dx $$

I suppose the region is this:

$D=\{ (x,y) \in \Bbb R^2 \mid 1+x \le y \le 1$ $ \&$ $ -1\le x \le 1 \}$

But I am not able to understand the region as $x \gt 0 $ and $ 1+x \le y \le 1$ , this is not making sense.

If possible please explain the region graphically.

Edit:

As in comments , i understood the above question.

Now i want to compute the integral using transformation $x +y = u$ and $y-x = v$.

So what is the corresponding region in $uv$ plane.

Please provide the solution to this integral using the transformation.