Sketching Region for |x-y|+|x|-|y| <= 2

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To sketch the region defined by the inequality |x-y| + |x| - |y| ≤ 2, it is effective to break it down into four cases based on the signs of x and y. Each case leads to a simplified linear inequality that describes a specific region in the plane. The combined result of these cases reveals a diamond-shaped area with vertices at (1,0), (0,1), (-1,0), and (0,-1). Visualizing this region can be aided by plotting the boundaries derived from each case. This method provides a clear understanding of the solution space for the given inequality.
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i want to sketch the region in the plane consisting of all points (x,y) for

|x-y|+|x|-|y| <= 2

any ideas?
thanks
 
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Welcome penguin devil !:wink:

Sketch each term separately, it will then be easy for you to sketch the linear combination. We do only provide hints !

_________________
You need 3D sketch of course...
 


To sketch this region, we can start by breaking the inequality into four separate cases based on the absolute value expressions.

Case 1: x ≥ 0, y ≥ 0
In this case, the inequality becomes x-y+x-y ≤ 2, or 2x-2y ≤ 2. Simplifying further, we get x-y ≤ 1. This represents the region above the line y=x-1.

Case 2: x ≥ 0, y < 0
Following the same steps as above, we get x+y+x-y ≤ 2, or 2x ≤ 2. This represents the region to the right of the y-axis and below the line x=1.

Case 3: x < 0, y ≥ 0
Similarly, we get -x-y-x-y ≤ 2, or -2y ≤ 2. Simplifying, we get y ≥ -1. This represents the region to the left of the x-axis and above the line y=-1.

Case 4: x < 0, y < 0
Again, following the same steps, we get -x+y-x+y ≤ 2, or 2y ≤ 2. Simplifying, we get y ≤ 1. This represents the region below the line y=x+1.

Combining all four cases, we get a region in the plane that looks like a diamond shape with its corners at (1,0), (0,1), (-1,0), and (0,-1). See the attached image for a visual representation.

I hope this helps!
 
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