Simplify: a+ba2−b2\frac{a+b}{a^2 - b^2}a2−b2a+b (assume a≠±ba \neq \pm ba=±b).
1a−b\frac{1}{a-b}a−b1
1a+b\frac{1}{a+b}a+b1
a−ba - ba−b
a+ba−b\frac{a+b}{a-b}a−ba+b