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De Moivre's Theorem Calculator

De Moivre's Theorem:

\[ (r (\cos \theta + i \sin \theta))^n = r^n (\cos (n \theta) + i \sin (n \theta)) \]

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1. What is De Moivre's Theorem?

De Moivre's Theorem is a formula that connects complex numbers and trigonometry. It states that for any real number θ and integer n, the following holds:

\[ (r (\cos \theta + i \sin \theta))^n = r^n (\cos (n \theta) + i \sin (n \theta)) \]

2. How Does the Calculator Work?

The calculator applies De Moivre's Theorem to compute:

\[ (r (\cos \theta + i \sin \theta))^n = r^n (\cos (n \theta) + i \sin (n \theta)) \]

Where:

Explanation: The theorem allows easy computation of powers and roots of complex numbers in polar form.

3. Importance of De Moivre's Theorem

Details: This theorem is fundamental in complex number theory, electrical engineering, and physics. It simplifies complex number exponentiation and helps find roots of complex numbers.

4. Using the Calculator

Tips: Enter the magnitude (r > 0), angle in radians, and the exponent n. The calculator provides results in both polar and rectangular (a + bi) forms.

5. Frequently Asked Questions (FAQ)

Q1: Can n be a fractional number?
A: Yes, De Moivre's Theorem works for any real number n, including fractions (which correspond to roots).

Q2: What if my angle is in degrees?
A: Convert degrees to radians first (multiply by π/180) before using the calculator.

Q3: Can r be negative?
A: No, r represents magnitude and must be positive. Negative magnitudes are not meaningful in polar form.

Q4: How is this used in real applications?
A: It's used in signal processing, electrical engineering (AC circuit analysis), and quantum mechanics.

Q5: What about Euler's formula?
A: De Moivre's Theorem is essentially the integer version of Euler's formula \( e^{iθ} = \cos θ + i \sin θ \).

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