Question
Use the imaginary number \( i \) to rewrite the expression below as a complex number. Simplify all radicals. \[ -3+\sqrt{-4} \]
Ask by Medina Young. in the United States
Jan 24,2025
Real Tutor Solution
Tutor-Verified Answer
Answer
\(-3 + 2i\)
Solution
To rewrite the expression \(-3 + \sqrt{-4}\) as a complex number using the imaginary unit \( i \), follow these steps:
1. **Express \(\sqrt{-4}\) in terms of \( i \):**
The imaginary unit \( i \) is defined as \( i = \sqrt{-1} \). Therefore, we can rewrite \(\sqrt{-4}\) as:
\[
\sqrt{-4} = \sqrt{4 \times (-1)} = \sqrt{4} \times \sqrt{-1} = 2i
\]
2. **Substitute back into the original expression:**
\[
-3 + \sqrt{-4} = -3 + 2i
\]
3. **Final Complex Number:**
The expression simplified as a complex number is:
\[
-3 + 2i
\]
This is in the standard form \( a + bi \), where:
- \( a = -3 \) (the real part)
- \( b = 2 \) (the imaginary part)
**Answer:** \(-3 + 2i\)
Reviewed and approved by the UpStudy tutoring team
Like
error msg
Explain
Simplify this solution
The Deep Dive
To rewrite the expression \( -3+\sqrt{-4} \) as a complex number, we first recognize that the square root of a negative number can be expressed using the imaginary unit \( i \). We know that \( \sqrt{-4} = \sqrt{4} \cdot \sqrt{-1} = 2i \). Therefore, we can substitute this back into the expression: \[ -3 + \sqrt{-4} = -3 + 2i \] Thus, the simplified expression in complex number form is: \[ -3 + 2i \]