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Ch. 1 - Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 2, Problema 25

Divide and express the result in standard form. 8i/(4 - 3i)

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1
Identify the problem: You need to divide the complex number \$8i$ by the complex number $(4 - 3i)$ and express the result in standard form, which is $a + bi$ where $a$ and $b$ are real numbers.
To divide complex numbers, multiply the numerator and denominator by the conjugate of the denominator. The conjugate of \((4 - 3i)\) is \((4 + 3i)\). So multiply both numerator and denominator by \((4 + 3i)\):
\[\frac{8i}{4 - 3i} \times \frac{4 + 3i}{4 + 3i}\]
Use the distributive property (FOIL) to expand both the numerator and the denominator:
- Numerator: \(8i \times (4 + 3i)\)
- Denominator: \((4 - 3i)(4 + 3i)\)
Simplify the denominator using the difference of squares formula: \((a - bi)(a + bi) = a^2 + b^2\). Here, \(a=4\) and \(b=3\), so the denominator becomes \(4^2 + 3^2\).

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