What is the quotient of the complex number [tex]$4-3i$[/tex] divided by its conjugate?

A. [tex]\frac{24}{25}+\frac{7}{25}i[/tex]
B. [tex]\frac{7}{25}+\frac{24}{25}i[/tex]
C. [tex]\frac{24}{25}-\frac{7}{25}i[/tex]
D. [tex]\frac{7}{25}-\frac{24}{25}i[/tex]



Answer :

To determine the quotient of the complex number [tex]\( 4 - 3i \)[/tex] divided by its conjugate, we can follow these steps:

1. Identify the conjugate of the complex number:
The conjugate of [tex]\( 4 - 3i \)[/tex] is [tex]\( 4 + 3i \)[/tex].

2. Set up the division:
We need to compute:
[tex]\[ \frac{4 - 3i}{4 + 3i} \][/tex]

3. Rationalize the denominator:
To simplify this expression, we multiply the numerator and the denominator by the conjugate of the denominator:
[tex]\[ \frac{4 - 3i}{4 + 3i} \times \frac{4 - 3i}{4 - 3i} \][/tex]

4. Multiply the numerators and denominators:
The numerator becomes:
[tex]\[ (4 - 3i)(4 - 3i) = 16 - 12i - 12i + 9i^2 = 16 - 24i + 9(-1) = 16 - 24i - 9 = 7 - 24i \][/tex]

The denominator becomes:
[tex]\[ (4 + 3i)(4 - 3i) = 16 - 9i^2 = 16 - 9(-1) = 16 + 9 = 25 \][/tex]

5. Rewrite and simplify the expression:
Combining the results from the numerator and the denominator, we get:
[tex]\[ \frac{4 - 3i}{4 + 3i} = \frac{7 - 24i}{25} = \frac{7}{25} - \frac{24}{25}i \][/tex]

6. Final result:
The quotient of [tex]\( 4 - 3i \)[/tex] divided by its conjugate is:
[tex]\[ \frac{7}{25} - \frac{24}{25}i \][/tex]

This matches the third option in the list given:
[tex]\[ \boxed{\frac{7}{25} - \frac{24}{25}i} \][/tex]