Find All Solutions of the Equation $$x ^ { 4 } + 16 = 0$$

question 145

Multiple Choice

Find all solutions of the equation. Leave answers in trigonometric form.
- $$x ^ { 4 } + 16 = 0$$

• A) \(\left\{ 2 \operatorname { cis } 45 ^ { \circ } , 2 \operatorname { cis } 315 ^ { \circ } , 2 \right.\) cis \(135 ^ { \circ } , 2\) cis \(\left. 225 ^ { \circ } \right\}\)
• B) \(\left\{ \sqrt { 3 } \operatorname { cis } 26.565 ^ { \circ } , \sqrt { 3 } \operatorname { cis } 333.435 ^ { \circ } , \sqrt { 3 } \operatorname { cis } 153.435 ^ { \circ } , \sqrt { 3 } \operatorname { cis } 206.565 ^ { \circ } \right\}\)
• C) \(\left\{ 16 \operatorname { cis } 45 ^ { \circ } , 16 \operatorname { cis } 315 ^ { \circ } , 16 \right.\) cis \(135 ^ { \circ } , 16\) cis \(\left. 225 ^ { \circ } \right\}\)
• D) \(\left\{ \sqrt { 2 } \operatorname { cis } 45 ^ { \circ } , \sqrt { 2 } \operatorname { cis } 315 ^ { \circ } , \sqrt { 2 } \operatorname { cis } 135 ^ { \circ } , \sqrt { 2 } \operatorname { cis } 225 ^ { \circ } \right\}\)