[问答题]
The function f is 3t:m4uifz rb0bpe bu-:q *;sg+y u1qxr ,grw ew z.(n ;(7;dfa1nzfymgiven by $f(x)=\frac{4 x^{2}-128}{x^{2}-16}$ , for $x \neq \pm 4$ .
1. Prove that f is an even function.
2. 1. Sketch the graph of y=f(x) .
2. Write down the range of f .
