Hello! To solve this exercise, we must remember about Complex Numbers and Real Numbers. To understand it better, look to the image below:
Knowing it, let's analyze each number and classify them:
• -12 is a real number
• 0 + 9i = 9i is a non-real complex number
• i^6 = -1 is a real number
• 7 -5i is a non-real number
• -i² + i³ is a non-real number
,
•
![\sqrt[]{(-5)^2}=\sqrt[]{25}=5\text{ is a real number}](https://img.qammunity.org/2023/formulas/mathematics/college/y8dosf450uba9sqebbunxd8zuzibjlhyc9.png)
![2-7i^2=9\text{ is a real number}](https://img.qammunity.org/2023/formulas/mathematics/college/qkiv9lwnhn8y30br35nialldk87ohjnc50.png)
![\sqrt[]{-6}\text{ is a non-real complex number}](https://img.qammunity.org/2023/formulas/mathematics/college/qqzoh316dq7hjgl1zbjmeg3qgjeer7uo6r.png)