a-b=5,a^2+b^2=13 (a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)

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a-b=5,a^2+b^2=13(a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)a-b=5,a^2+b^2=13(a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)

a-b=5,a^2+b^2=13 (a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)
a-b=5,a^2+b^2=13 (a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)

a-b=5,a^2+b^2=13 (a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)
(a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)
=a^3-2b^3-a^2b+2ab^2-ab^2+b^3
=a^3-b^3-a^2b+ab^2
=(a^3-b^3)-(a^2b-ab^2)
=(a-b)(a^2+b^2+ab)-ab(a-b)
=5(13+ab)-ab*5
=65

(a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)
=a^3-2b^3-a^2b+2ab^2-ab^2+b^3
=a^3-b^3-a^2b+ab^2
=(a^3-b^3)-(a^2b-ab^2)
=(a-b)(a^2+b^2+ab)-ab(a-b)
=5(13+ab)-ab*5
=65

(a-b)^2-(a^2+b^2)=25-13
-2ab=12
ab=-6
(a^3-2b^3)-(a^2b-2ab^2)-(ab^2-b^3)
=a^3-2b^3-a^2b+2ab^2-ab^2+b^3
=a^3-b^3-a^2b+ab^2
=(a-b)(a^2+b^2+ab)-ab(a-b)
=5(13-6)+6*5
=65