a^-a-b^-b/a^+a-b^+b
=[(a²-b²)-(a+b)]/[(a²-b²)+(a+b)]
=(a+b)(a-b-1)/(a+b)(a-b+1)
=(a-b-1)/(a-b+1)
a^-a-b^-b/a^+a-b^+b分式的约分
a^-a-b^-b/a^+a-b^+b
=[(a²-b²)-(a+b)]/[(a²-b²)+(a+b)]
=(a+b)(a-b-1)/(a+b)(a-b+1)
=(a-b-1)/(a-b+1)