一道数学题 急!!!!!!!!!!!!

(a/a-b - a²/a²-2ab+b²) -(a/a+b - a²/a²-b²)+1
=(a/(a-b)-a^2/(a-b)^2)-(a/(a+b)-a^2/(a-b)(a+b))+1
=(a^2-ab-a^2)/(a-b)^2-(a^2-ab-a^2)/(a-b)(a+b)+1
=ab(1/(a-b)(a+b)-1/(a-b)^2)+1
=ab*((a-b)-(a+b))/(a-b)^2(a+b)+1
=-2ab^2/(a-b)^2(a+b)+1
=-2*2/3*9/(2/3+3)^2(2/3-3)+1
=-108/77+1
=-31/77

=1-b-1-2ab+b²-1-b+1+b²+1
=-2ab-2b+2b²+1
=2b(b-1-a)+1
=-6(-3-1-2/3)+1
=29

(a/a-b - a2/a2-2ab+b2) -(a/a+b - a2/a2-b2)+1

=a/(a-b)-a2/(a-b)2-(a/(a+b)-a2/(a+b)(a-b))+1

=(a(a-b)-a2)/(a-b)2-(a(a-b)-a2)/(a+b)(a-b)+1

=(-ab)/(a-b)2+ab/(a+b)(a-b)+1

=-ab*[(a+b)+(a-b)]/(a+b)(a-b)2+1

=-2a2b/(a+b)(a-b)2+1

=-2*4/9*(-3)/(2/3-3)(2/3+3)2+1

=775/847

=(b²-2ab-b)-(b-b²)+1
=2b²-2ab+1
=2*9-2*2/3*(-3)+1
=23

你能不能把括号弄好啊 ！
[a/(a-b)-a²/(a-b)²]-[a/(a+b)-a²/(a+b)(a-b)]+1
={[a(a-b)-a&