(a+b/a-b)² * 2a-2b/3a+3b - a²/a²-b² ÷ a/b

(a+b/a-b)² * 2a-2b/3a+3b - a²/a²-b² ÷ a/b

The original formula = [(a + b) & sup2; / (a-b) & sup2;] * [2 (a-b) / 3 (a + b)] - [A & sup2; / (a + b) (a-b)] × (B / a) = 2 (a + b) / 3 (a-b) - AB / (a + b) (a-b) = [(2a & sup2; + 4AB + 2B & sup2; - 3AB) / 3 (a + b) (a-b) = (2a & sup2; + AB + 2B & sup2;) / (3a & sup2; - 3b & sup2;)