Answer:
[tex]y\in(-\infty, -2)\cup(-2,2)\cup (2,\infty)[/tex]
Step-by-step explanation:
Consider expression:
[tex]\dfrac{4}{y+2}-\dfrac{3}{y-2}+\dfrac{12}{y^2-4}[/tex]
This expression consists of three fractions.
1st fraction has [tex]y+2[/tex] in denominator. Denominator cannot be equal to 0, so
[tex]y+2\neq 0\\ \\y\neq -2[/tex]
2nd fraction has [tex]y-2[/tex] in denominator. Denominator cannot be equal to 0, so
[tex]y-2\neq 0\\ \\y\neq 2[/tex]
3rd fraction has [tex]y^2-4[/tex] in denominator. Denominator cannot be equal to 0, so
[tex]y^2-4\neq 0\\ \\y\neq \pm 2[/tex]
Hence, the domain is
[tex]y\in(-\infty, -2)\cup(-2,2)\cup (2,\infty)[/tex]