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Precalculus

Course: Precalculus > Unit 3

Lesson 5: Modulus (absolute value) and argument (angle) of complex numbers
Math
Precalculus
Complex numbers
Modulus (absolute value) and argument (angle) of complex numbers
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Angle of complex numbers

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Problem

z, equals, 8, minus, 9, i

Find the angle theta (in radians) that z makes in the complex plane.
Round your answer, if necessary, to the nearest thousandth. Express theta between minus, pi and pi.
theta, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
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