Questions: Perform the indicated operations.
[
frac-7-sqrt-1842
]
Transcript text: Perform the indicated operations.
\[
\frac{-7-\sqrt{-18}}{42}
\]
Solution
Solution Steps
To solve the given expression, we need to simplify the square root of a negative number using imaginary numbers. Then, perform the arithmetic operations to simplify the fraction.
Step 1: Simplify the Square Root of a Negative Number
The expression involves the square root of a negative number, \(\sqrt{-18}\). This can be expressed using imaginary numbers as \(\sqrt{-18} = \sqrt{18} \cdot i\), where \(i\) is the imaginary unit. Calculating \(\sqrt{18}\), we have:
\[
\sqrt{18} = \sqrt{9 \times 2} = 3\sqrt{2} \approx 4.2426
\]
Thus, \(\sqrt{-18} \approx 4.2426i\).
Step 2: Substitute and Simplify the Expression
Substitute \(\sqrt{-18} \approx 4.2426i\) into the original expression:
\[
\frac{-7 - \sqrt{-18}}{42} = \frac{-7 - 4.2426i}{42}
\]
Step 3: Perform the Division
Divide both the real and imaginary parts of the numerator by the denominator:
\[
\frac{-7}{42} = -0.1667
\]
\[
\frac{-4.2426i}{42} \approx -0.1010i
\]
Thus, the expression simplifies to:
\[
-0.1667 - 0.1010i
\]
Final Answer
The simplified form of the expression is:
\[
\boxed{-0.1667 - 0.1010i}
\]