Question

under what condition is a2+ab+b2/a2-b2 undefined?

Answer 1

Given: the denominator cannot equal zero.

$a^2-b^2=0\\a=b\\a^2-a^2=0$

The function $\frac{a^2+ab+b^2}{a^2-b^2}$ is undefined under the condition that a = b.