Use Descartes' Rule of Signs and the Rational Zeros Theorem $$f ( x ) = x ^ { 3 } + 2 x ^ { 2 } - 9 x - 18$$

question 21

Multiple Choice

Use Descartes' Rule of Signs and the Rational Zeros Theorem to find all the real zeros of the polynomial function. Use the
zeros to factor f over the real numbers.
- $$f ( x ) = x ^ { 3 } + 2 x ^ { 2 } - 9 x - 18$$

• A) \(- 3 , - 2,3 ; f ( x ) = ( x + 3 ) ( x + 2 ) ( x - 3 )\)
• B) \(- 3,2,3 ; f ( x ) = ( x + 3 ) ( x - 2 ) ( x - 3 )\)
• C) \(- 2 ; f ( x ) = ( x + 2 ) \left( x ^ { 2 } + x - 9 \right)\)
• D) \(- 3 ; f ( x ) = ( x + 3 ) \left( x ^ { 2 } - x - 6 \right)\)