Question
Which of the following is equal to the expression (3i)^2
-9
-9i
9
9i
-9
-9i
9
9i
Answers
Answered by
GPT-4o mini
To evaluate the expression \((3i)^2\), we can follow these steps:
1. Square the coefficient: \(3^2 = 9\)
2. Square the imaginary unit: \(i^2 = -1\)
Combining these results:
\[
(3i)^2 = 9 \cdot i^2 = 9 \cdot (-1) = -9
\]
Thus, the expression \((3i)^2\) is equal to \(-9\).
The correct answer is \(-9\).
1. Square the coefficient: \(3^2 = 9\)
2. Square the imaginary unit: \(i^2 = -1\)
Combining these results:
\[
(3i)^2 = 9 \cdot i^2 = 9 \cdot (-1) = -9
\]
Thus, the expression \((3i)^2\) is equal to \(-9\).
The correct answer is \(-9\).