Simplification and calculation Calculate that the square of a minus the square of B plus the square of 2B minus 1 / a minus the square of B plus a plus B, where a plus B equals 2000

The original formula = [A & sup2; - (B & sup2; - 2b + 1)] / [(a + b) (a-b) + A + b]
=[a²-(b-1)²]/[(a+b)(a-b+1)]
=(a+b-1)(a-b+1)/[(a+b)(a-b+1)]
=(a+b-1)/(a+b)
=(2000-1)/2000
=1999/2000

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