Question

a supra a -b minus b supra a+b

Answer 1

 [tex]\frac{a}{a-b}-\frac{b}{a+b}\;\;\rightarrow\;\;\frac{a(a+b)-b(a-b)}{a^2-b^2}=\frac{a^2+ab-ab+b^2}{a^2-b^2}=\frac{a^2+b^2}{a^2-b^2}\;\\ [/tex]