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1 vote
Two complex numbers are being divided as shown below.

16-3i
2 + 14i
Part A:
What is the complex conjugate of the denominator?
Part B:
What is the quotient of these complex numbers written in standard (a + bi)?

User ArunGJ
by
7.7k points

1 Answer

4 votes

Part A: The complex conjugate is
\(2 - 14i\).

Part B: The final answer in standard form (a + bi) is
\[ -(1)/(20) - (23)/(20)i \]

How did we get the values?

Given complex numbers:


\( (16 - 3i)/(2 + 14i) \)

Part A: Complex Conjugate of the Denominator

The complex conjugate of a complex number
\(a + bi\) is
\(a - bi\). For the given denominator
\(2 + 14i\), the complex conjugate is
\(2 - 14i\).

Part B: Quotient in Standard Form (a + bi)

To find the quotient, we need to multiply the given expression by the conjugate of the denominator over itself. This is done to eliminate the imaginary part from the denominator.


\[ (16 - 3i)/(2 + 14i) \cdot (2 - 14i)/(2 - 14i) \]

Now, multiply the numerators and denominators:

Numerator:
\( (16 - 3i)(2 - 14i) = 32 - 224i - 6i + 42i^2 \)

Simplify:
\( 32 - 230i - 42 \) (because
\(i^2 = -1\))

Combine like terms:
\( -10 - 230i \)

Denominator:
\( (2 + 14i)(2 - 14i) = 4 - 196i^2 \)

Simplify:
\( 4 + 196 \) (because
\(i^2 = -1\))

Combine like terms:
\( 200 \)

Now, the quotient is:


\[ (-10 - 230i)/(200) \]

Simplify the fraction by dividing both the real and imaginary parts by 10:


\[ (-1 - 23i)/(20) \]

So, the final answer in standard form (a + bi) is:


\[ -(1)/(20) - (23)/(20)i \]

User Thorsten Dittmar
by
8.6k points