Find the given power and write the answer in rectangular notation.

[tex]\[
\left(\cos 60^{\circ}+i \sin 60^{\circ}\right)^6
\][/tex]

(Simplify your answer, including any radicals. Use integers or fractions for any numbers in the expression. Type your answer in the form [tex]\(a + bi\)[/tex].)



Answer :

To solve the expression [tex]\((\cos 60^\circ + i \sin 60^\circ)^6\)[/tex] and write the answer in rectangular notation, follow these steps:

1. Identify the Components:
- The angle [tex]\(\theta\)[/tex] is [tex]\(60^\circ\)[/tex].
- We need to convert this angle to radians for computations: [tex]\( \theta = 60^\circ \)[/tex].

2. Calculate the Real and Imaginary Parts (Cosine and Sine of the Angle):
[tex]\[ \cos 60^\circ = 0.5 \][/tex]
[tex]\[ \sin 60^\circ = \sqrt{3}/2 \approx 0.866 \][/tex]

3. Apply De Moivre’s Theorem:
De Moivre's theorem states that for a complex number in polar form:
[tex]\[ (r (\cos \theta + i \sin \theta))^n = r^n (\cos(n \theta) + i \sin(n \theta)) \][/tex]
In our case, [tex]\(r = 1\)[/tex] (since the modulus of our complex number is 1), [tex]\(\theta = 60^\circ\)[/tex], and [tex]\(n = 6\)[/tex]:
[tex]\[ (\cos 60^\circ + i \sin 60^\circ)^6 = \cos (6 \cdot 60^\circ) + i \sin (6 \cdot 60^\circ) \][/tex]

4. Calculate the New Angle:
[tex]\[ 6 \cdot 60^\circ = 360^\circ \][/tex]
Reducing [tex]\(360^\circ\)[/tex] modulo [tex]\(360^\circ\)[/tex] gives [tex]\(0^\circ\)[/tex].

5. Evaluate the Cosine and Sine for the New Angle:
[tex]\[ \cos 360^\circ = \cos 0^\circ = 1 \][/tex]
[tex]\[ \sin 360^\circ = \sin 0^\circ = 0 \][/tex]

6. Combine the Results in Rectangular Form:
[tex]\[ \cos(360^\circ) + i \sin(360^\circ) = 1 + 0i = 1 \][/tex]

Therefore, the value of [tex]\((\cos 60^\circ + i \sin 60^\circ)^6\)[/tex] in rectangular form is:
[tex]\[ 1 + 0i \quad \text{or simply} \quad 1 \][/tex]

So the final simplified answer in rectangular form is [tex]\( \boxed{1} \)[/tex].