Find All Values Of $X$ Such That $f ( x ) > 0$

question 13

Multiple Choice

Find all values of $X$ such that $f ( x ) > 0$ $f ( x ) = x ^ { 4 } - 16 x ^ { 2 }$

• A) \(( - \infty , 4 ) \cup ( 4 , \infty )\)
• B) \(( - \infty , - 4 ] \cup [ 4 , \infty )\)
• C) \(( - 4,4 )\)
• D) \(( - \infty , 4 ) \cup ( - 4 , \infty )\)
• E) \(( - \infty , - 4 ) \cup ( 4 , \infty )\)