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Write the following expression as a single complex number.

1-2i/3-2i
a. 7/5 -4/5i
b. -1/5-4/5i
c. -1/13-4/13i
d. 7/13-4/12i

User Lea Hayes
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1 Answer

4 votes

Final answer:

To simplify the complex expression (1-2i)/(3-2i), we multiply numerator and denominator by the complex conjugate (3+2i), which results in the simplification to a single complex number 7/13 - 4/13i. However, a typo in the question options suggests the correct answer as (-1/13 - 4/13i) instead of (7/13 - 4/13i). option d is the correct answer.

Step-by-step explanation:

The question asks us to simplify the complex expression 1-2i/3-2i. To express it as a single complex number, we can use a method called complex conjugation. The complex conjugate of the denominator (3-2i) is 3+2i. We multiply both the numerator and the denominator by this conjugate.

The multiplication process is as follows:

(1 - 2i)(3 + 2i) / (3 - 2i)(3 + 2i)

This simplifies to:

(3 + 2i - 6i - 4i²) / (9 + 6i - 6i - 4i²)

Recognizing that i² = -1, we continue simplifying:

(3 - 4i² - 4i) / (9 - 4i²)

Which further simplifies to:

(3 + 4 - 4i) / (9 + 4)

Thus, the single complex number would be:

7/13 - 4/13i

So the correct answer is c. -1/13-4/13i, but due to the positive results of real part calculation, the answer should have been d. 7/13 - 4/13i instead.

User Jeffrey Fulton
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