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This picture shows roughly the area we want to integrate in(I am very very poor at drawing)
We have to use a variable change to solve the problem
Let x x 2 + y 2 = u and y x 2 + y 2 = v
∣ ∣ ∣ ∣ ∂ ( x , y ) ∂ ( u , v ) ∣ ∣ ∣ ∣ = ( x y x 2 + y 2 ) 2
So ∣ ∣ ∣ ∣ ∂ ( u , v ) ∂ ( x , y ) ∣ ∣ ∣ ∣ = ( x 2 + y 2 x y ) 2
So after this our integral just becomes a really simple one:
∬ E x y 1 d x d y = ∬ T x y 1 ( x 2 + y 2 x y ) 2 d u d v = ∬ T ( x 2 + y 2 ) 2 x y d u d v
Where T is the rectangular region in u v plane given by 1 ≤ u ≤ 2 and 1 ≤ v ≤ 2
So we have :- ∫ 1 2 ∫ 1 2 u v 1 d u d v
So A = ( ln ( 2 ) ) 2
⌊ 1 0 0 0 A ⌋ = 4 8 0