Given fraction is
[tex]f(x) = \frac{x^2 + 4x + 3}{x^2 - 9} [/tex]
As we know fraction is not defined where denominator is equal to zero.
So let's find where denominator is zero.
[tex]x^2 - 9 = 0[/tex]
We can factorize it as [tex]a^2 - b^2 = (a+b)(a - b)[/tex]
So we can write given equation as
[tex](x+3)(x-3) = 0[/tex]
So x = 3 or x = -3.
So function is undefined at x = 3 and x = -3.
So option 3 is correct.
