Answer :

To express the complex number [tex]\(\frac{3 + 10i}{9 - i}\)[/tex] in the form [tex]\(a + bi\)[/tex], follow these steps:

1. Identify the given complex division:
[tex]\[ \frac{3 + 10i}{9 - i} \][/tex]

2. Multiply the numerator and the denominator by the conjugate of the denominator:
The conjugate of [tex]\(9 - i\)[/tex] is [tex]\(9 + i\)[/tex].

Multiply both the numerator and the denominator by [tex]\(9 + i\)[/tex]:
[tex]\[ \frac{(3 + 10i)(9 + i)}{(9 - i)(9 + i)} \][/tex]

3. Simplify the denominator:
The denominator is a product of a complex number and its conjugate:
[tex]\[ (9 - i)(9 + i) = 9^2 - (-i^2) = 81 + 1 = 82 \][/tex]

4. Expand and simplify the numerator:
Multiply each term in the numerator:
[tex]\[ (3 + 10i)(9 + i) = 3 \cdot 9 + 3 \cdot i + 10i \cdot 9 + 10i \cdot i = 27 + 3i + 90i + 10i^2 \][/tex]
Recall that [tex]\(i^2 = -1\)[/tex], so:
[tex]\[ 10i^2 = 10(-1) = -10 \][/tex]
Combining all terms:
[tex]\[ 27 + 3i + 90i - 10 = 17 + 93i \][/tex]

5. Express the resulting fraction:
[tex]\[ \frac{17 + 93i}{82} \][/tex]

6. Separate the real and imaginary parts:
Divide both parts of the numerator by the denominator:
[tex]\[ \frac{17}{82} + \frac{93i}{82} \][/tex]

7. Simplify the division:
Simplify each division to decimal form:
[tex]\[ \frac{17}{82} \approx 0.2073170731707317 \][/tex]
[tex]\[ \frac{93}{82} \approx 1.1341463414634148 \][/tex]

Therefore, the complex number [tex]\(\frac{3 + 10i}{9 - i}\)[/tex] in the form [tex]\(a + bi\)[/tex] is:

[tex]\[ 0.2073170731707317 + 1.1341463414634148i \][/tex]

So, the solutions are:
[tex]\[ a \approx 0.2073170731707317 \][/tex]
[tex]\[ b \approx 1.1341463414634148 \][/tex]

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