Putnam 1988

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Problem A1

Let S = { (x, y) : |x| - |y| ≤ 1 and |y| ≤ 1 }. Sketch S and find its area.

 

Solution

Answer: 6.

Trivial.

The region is the rectangle (-2, 1), (2, 1), (2, -1), (-2, -1) less the two triangles (2, 1), (1, 0), (2, -1) and (-2, 1), (-1, 0), (-2, -1). Hence the area is 8 - 2.1 = 6.

 


 

Putnam 1988

© John Scholes
jscholes@kalva.demon.co.uk
12 Dec 1998