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Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Non è quello che usi tu?Cambia libro di testo
Capitolo 5, Problema 5.1.61

Evaluate x²+19 / 2−x for x = 3i.

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1
Identify the given expression: \(\frac{x^2 + 19}{2 - x}\) and the value of \(x = 3i\), where \(i\) is the imaginary unit with the property \(i^2 = -1\).
Substitute \(x = 3i\) into the numerator: calculate \(x^2 + 19\) by first finding \(x^2 = (3i)^2\) and then adding 19.
Substitute \(x = 3i\) into the denominator: calculate \(2 - x = 2 - 3i\).
Simplify the numerator using the fact that \(i^2 = -1\), so \((3i)^2 = 9i^2 = 9(-1) = -9\), then add 19 to get the numerator value.
Write the expression as a complex fraction with the simplified numerator and denominator, and if needed, multiply numerator and denominator by the conjugate of the denominator to simplify the expression further.

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